Soft and fluffy blueberry donut bars filled with blueberry curd and whipped cream, topped off with a blueberry glaze.
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blueberry donut bars
Hello hello! ☺︎ Today I have for you the perfect light spring donut that is perfect for blueberry lovers: these blueberry donut bars (or blueberry long johns, if you’re in the midwest like me!) It starts off with a super fluffy brioche dough that gets fried and filled with blueberry curd and freshly whipped cream, and it gets glazed with a blueberry glaze that’s naturally and beautifully pink.
There’s definitely a few components to this recipe but to make it less daunting you can make the dough and blueberry curd the night before to fry and finish them off the next day. I know donuts can feel a little intimidating but I’ve got allllll the tips and tricks you need to successfully make these below. So let’s get into it!
why you’ll love these blueberry donut bars:
- They’re super soft and fluffy: the dough is a brioche dough – meaning it’s enriched with milk, eggs & butter.
- Blueberry curd & blueberry glaze: two types of blueberry components for maximum blueberry flavor.
expert baking tips
Weigh your ingredients:
My recipes are all written in grams because it is the most accurate way to bake. When you use a kitchen scale, you ensure that your baked goods turn out as close to the written recipe as possible. Plus, the cleanup is way easier when using a scale! I will provide standard cup measurements but please note that I have not tested the recipe using cup measurements and therefore can not guarantee your recipe will come out how mine did. Here is my favorite kitchen scale.
Use room temperature ingredients:
It’s important that your ingredients are at room temperature so that they can easily incorporate with each other. Take out your cold ingredients about an hour before you’ll need them.
the dough will take a while to knead
Kneading this dough will take a longer time than you are probably used to. This dough is enriched with eggs and butter which makes it take longer for the proper amount of gluten to develop. Kneading in the mixer can take me anywhere from 10-20 minutes. The dough is ready to be used when it passes the windowpane test and has pulled away from the sides and bottom of the bowl. If you are weighing your ingredients, just trust the process! If you are using cup measurements and the dough just is not coming together after 15 minutes, try adding in 1 tbsp. of flour at a time.
be careful heating the milk
Heating the milk is important for bringing the yeast to an optimal temperature for rising. The milk should be heated to ~100°F / 38°C but it does not have to be exact. As long as the milk is between 95°F – 110°F, it is good to be used. If the temperature exceeds 110°F, wait for it to cool down before using so that you do not kill the yeast!
how to tell your dough is done kneading: the windowpane test
The windowpane test is (in my opinion) the best way to tell that your dough has been properly kneaded. Once the dough starts to pull away from the sides and the bottom of the mixing bowl, it is most likely ready. However, just to be sure that it’s good to go I check if it passes the windowpane test. To do that, take some of the dough in your hands and start to slowly stretch it out. If it can get thin enough to where light passes through it before tearing, then it’s good to go! If not, keep kneading until it does!
ingredients for blueberry donut bars:
Brioche donuts:
- Bread flour: for structure and chewiness. I recommend using bread flour because it has more protein which gives you a chewier, fluffier donut. You can use all purpose flour in it’s place, but please be sure that you are using a high-quality flour that has a high protein %, such as King Arthur (11.7%) so that your gluten will develop. If you’re using a low protein flour, the gluten will not develop enough and you will have to add a lot more flour to the brioche, which will alter the dough!
- Active dry yeast: for making the dough rise. You can easily substitute in instant yeast if that is what you have on hand. You will just skip the step of combining the warm milk, sugar, and yeast!
- Salt: for balancing and bringing out the sweetness of the brioche. Salt also “controls” the yeast to make sure that it does not overly expand.
- Granulated sugar: for sweetening the brioche and for helping the yeast with rising. We’ll also coat the donuts in some granulated sugar.
- Egg: for binding and adding moisture.
- Unsalted butter: for tenderizing the brioche rolls and giving them a buttery, melt-in-your-mouth feel. I would not recommend substituting in salted butter since salt is important to controlling yeast growth and the amount of salt in salted butter is quite variable.
- Whole milk: for tenderizing and hydrating the dough. Whole milk will provide the softest rolls because the extra fat helps tenderize the dough. You can however swap in 1%, 2% or your favorite non dairy milk alternative! Just note that the dough may be a little less soft and fluffy due to the varying fat content.
blueberry curd:
- Egg yolks: thickens up the curd.
- Granulated sugar: to sweeten and thicken up the curd.
- Lemon: we’ll be using both the zest and the juice for maximum flavor.
- Blueberries: I used and recommend frozen – but fresh blueberries would work as well.
- Salt: like with the dough, a bit of salt helps with the flavor and sweetness of the curd.
- Unsalted butter: helps thicken the curd and make it creamy. You can substitute in salted butter here, just be sure to omit the extra salt from the curd.
WHIPPED CREAM:
- Heavy whipping cream: the base of the whipped cream. You could use a non-dairy heavy whipping cream here!
- Granulated sugar: just a little bit, for a touch of sweetness.
- Vanilla: bean paste or extract, for flavor.
blueberry glaze:
- Blueberries: fresh or frozen, for flavor and color.
- Granulated sugar: just a little bit, to macerate the blueberries.
- Powdered sugar: the base of the glaze.
how to make blueberry donut bars:
Here are some of the photos of the process of making these donuts. The full recipe is at the end of this blog post!
- Make the brioche dough and let it rise until it doubles in size.
- Divide the dough into 6 pieces and roll them each out into a 4″ x 2″ rectangle and let them rest.
- Make the blueberry curd.
- Fry the donuts.
- Make whipped cream, then fold the blueberry curd into the cream and fill the donuts.
- Dip the donuts in the blueberry glaze, then serve and enjoy!
blueberry donut bars recipe q&a
how to store brioche donuts
Fried donuts are definitely going to taste the best the day that they are baked, and I highly *highly* recommend serving them on the same day. Filled, they can be stored in an airtight container for up to 2 hours at room temperature. I recommend filling them no more than 2 hours before serving so you don’t have to refrigerate them, which will change the texture a bit.
can I double this recipe?
Yes! I can’t emphasize using a kitchen scale enough for especially this recipe already, but if you are going to double or half the ingredients it is even more important that you weigh your ingredients. The dough is very hydrated and slight alterations can change the texture of the dough.
can I use instant yeast instead of active dry yeast?
Definitely – just pop all of the dough ingredients into your mixing bowl to start kneading! Just be sure to keep. an eye on the dough as it should double in size faster.
can I make the dough ahead of time?
Yes, and I highly recommend it! Brioche dough is a very enriched dough that can be hard to work with when warm. Simply knead the dough together, cover it, and leave it to rise in the fridge overnight.
my yeast mixture isn’t foaming, what should I do?
The mixture should start foaming around 5 minutes in. If it has not foamed after 10 minutes, the yeast is likely dead. You want to make sure that the milk temperature does not exceed 110°F / 43°C or it will kill the yeast. If you try it again and it still does not foam, the yeast you are using may be expired and you will want to purchase some more before proceeding.
why are my fried donuts hollow?
While they will still be delicious, this has happened to me and it’s definitely frustrating! This could either be that the donuts did not rise for long enough, or that you didn’t get enough air out of the dough when punching it down. Note that every environment is different and while they should only take ~60 & ~30 minutes for the first and second rise in a warm environment – it could take longer if your kitchen is on the colder side. The dough is ready once it has doubled in size!
tools and ingredients:
You can find all my favorite tools and ingredients that I use on my Amazon Storefront page, here!
other recipes you might enjoy:
did you make this recipe?
I’d love to see and know your thoughts! please leave a comment and review below, and tag me on instagram @freshbeanbakery. #freshbeanbakery
Blueberry Donut Bars
Ingredients
Brioche Donuts
- 80 g whole milk (⅓ c.)
- 1 tsp. active dry yeast
- 1 tbsp. granulated sugar
- 180 g bread flour (1 ½ c.)
- ½ tsp. salt
- 1 egg room temperature
- 56 g unsalted butter (4 tbsp.) room temperature
- vegetable oil for frying
Blueberry Curd
- 1 egg yolk
- 2 tbsp. granulated sugar
- 50 g frozen blueberries (⅓ c.)
- 2 tsp. lemon juice
- zest of ½ a small lemon
- ⅛ tsp. salt
- 14 g unsalted butter (1 tbsp.) room temperature
Whipped Cream
- 180 g heavy whipping cream (6 oz.)
- 1 tbsp. granulated sugar
- 1 vanilla
Blueberry Glaze
- 40 g blueberries (¼ c.) fresh or frozen
- 1 tbsp. granulated sugar
- 120 g powdered sugar (1 c.)
Instructions
Brioche Donuts
- In a microwave safe measuring cup, heat the milk to 100°F / 38°C. Whisk in the yeast and the sugar. Set aside until the mixture begins to foam. (~5 minutes)
- While waiting, add the flour, salt, egg, and butter to the bowl of a stand mixer fitted with the dough hook attachment. When the yeast mixture begins to foam, add it in to the rest of the ingredients.
- Knead the dough on low speed for 1 minute to allow the ingredients to come together. Increase the speed to medium-high and knead for an additional 10-20 minutes, or until the dough passes the windowpane test. (This will happen after the dough has cleaned the sides and bottom of the bowl)
- Once the dough is done kneading, butter the inside of the bowl, form the dough into a ball and place it back in the bowl. Then cover the mixing bowl with plastic wrap. At this point, you could set the dough in the fridge to rise overnight, or continue with completing the recipe in one day. If doing in one day, set the dough in a warm area and wait for it to double in size (~1 hour.)
Blueberry Curd
- While the dough is rising, make the blueberry curd. Add the egg yolk, sugar, blueberries, lemon juice, lemon zest, and salt into a small saucepan.
- Whisk the mixture constantly over medium heat, mashing the blueberries as they soften, until the mixture thickens and reaches a temperature of 170°F / 76°C.
- Remove the curd from the heat and pass it through a fine mesh into a small bowl. Add in the butter and mix until it has completely melted.
- Transfer the curd to an airtight container and store it in the fridge until you're ready to fill the donuts.
Shaping, Frying & Coating
- Cut out 6 parchment squares that are ~4" each and place them on to a lined baking tray.
- Once the dough has doubled in size, punch it down to remove excess air, then transfer it to a clean, lightly floured surface.
- Divide the dough into 6 equally sized pieces, roughly shaping them into a rectangle. Use a rolling pin to roll out each piece into a 4" x 2" rectangle, using your hands to gently smoosh the dough into the correct shape and size as needed.
- Transfer each donut bar to its own parchment square, then cover the donuts loosely with a towel. Allow them to rise in a warm environment for ~30 minutes, or until they have slightly puffed up the dough springs back slowly when poked.
- While the dough is rising, start on the blueberry glaze. Add the blueberries* and sugar to a small mixing bowl. Mash the blueberries, then set the mixture aside.
- Once the donuts have puffed up, fill a large saucepan with at least 2" of vegetable or any neutral oil. Heat the mixture to 350°F / 175℃
- Carefully place the donuts in to the fryer with the parchment paper (2-3 at a time, depending on what your pan can fit). After ~5-10 seconds, remove carefully remove the parchment from the donuts using metal tongs.
- Fry the donuts on each side for 2-3 minutes, or until they are a deep golden brown. You can also check if they are done by making sure the internal temperature is at least 190°F / 87°C.
- Remove the donuts from the oil and place them on a wire rack to cool. Fry the remaining donuts.
Whipped Cream
- Add the heavy whipping cream, sugar, and vanilla to a medium-sized mixing bowl. Use a hand mixer or a stand mixer fitted with the whisk attachment to beat the mixture until soft peaks form. Set aside in the fridge until you're ready to fill the donuts.
Blueberry Glaze
- Once the donuts have cooled to room temperature, finish making the blueberry glaze. Add the powdered sugar into the mashed blueberry mixture and stir until the mixture is cohesive. If the mixture is too thick, add a little bit of water or lemon juice to thin it out. If it is too thin, add some powdered sugar to thicken it up.
- Use a sharp knife to poke a hole in the top of each donuts.
- Dollop the blueberry curd into the whipped cream, then use a rubber spatula to make a couple of big folds in the cream to slightly combine the curd and cream. Transfer the mixture to a piping bag fitted with a round tip.
- Fill each donut generously with the whipped cream & blueberry curd, then dip the tops of the donuts into the blueberry glaze. Allow the glaze to set, then serve immediately and enjoy!
Notes
Nutrition
Please note that the nutrition facts are only an estimate and may vary based on different brands of ingredients and any substitutions made.
