Making the Dough

Chop the dried blueberries into 3-4 pieces, then place them in a bowl. Pour about a half cup of boiling water over them, and allow it to sit for 5 minutes, or until the blueberries are soft. Dump the blueberries in a fine mesh sieve and let the water drain off.

Melt the butter in a bowl and beat in the sugar until it’s fluffy. Add the sour cream, egg yolks, and vanilla. Stir until it’s all well combined, scraping down the sides of the bowl with a rubber spatula.

Add the flour, baking powder, and salt. Stir them into the wet ingredients until the flour is mostly incorporated. Add the blueberries and finish stirring the batter until there are not flour streaks left and the berries are well distributed throughout it.

Place the dough on a disc of plastic wrap and press it out so that it’s 1-2″ thick. Wrap it well and place it in the refrigerator for 1-2 hours, or up to 24. This time in the fridge will help the butter in the dough solidify and give you a firmer dough that’s easier to work with.

Rolling Out and Cutting the Donuts

Once the dough is chilled, sprinkle a surface with flour. Place the dough on it and roll it out to about an inch thick. Cut out as many 3-4 inch circles as possible, then use a 1 inch cutter to cut the center out of each.

Set the cut donuts aside, then press together all of the dough around the edges. Press them all together and re-roll the dough out again, and cut as many out as you can.

You can either press the donut holes back into the dough edges and re-cut them as donuts, or you can fry them.

Don’t re-roll the dough more than twice, as it can get tough and you’ll end up with chewy donuts.

Frying the Donuts

To fry the donuts, pour 3-4 inches of a neutral flavored, high-smoke point oil in a medium sized pot with high sides. Some oils that work well are canola, vegetable, peanut, sunflower, or avocado.

Place a candy/fry thermometer on the edge of the pot. Heat the oil over medium heat until it reaches 375°. Carefully place 2-3 donuts in the oil and cook them on the first side for 1 1/2 minutes. The temperature of the oil will drop some when the donuts are added.

Turn the donuts with a long handled wooden or metal fork (plastic will melt in the oil), then allow them to cook for another 1 to 1 1/2 minutes on the second side. The outside should be a deep golden brown.

Remove the donuts from the hot oil and place them on a baking rack placed over a baking sheet to catch any oil drips. Cut open one of the donuts to make sure that the inside is cooked through. If not, you’ll need to lower the temperature on the oil.

Allow the oil to the correct temperature, making it hotter or allowing it to cool some depending on how they cooked.

Glazing the Donuts

To glaze the donuts, heat 1/2 cup of milk in a small pot until it’s steaming but not boiling. Whisk in 4 cups of powdered sugar, a bit at a time, until you have a glaze that runs easily but doesn’t look milky. Whisk in the vanilla extract or bean paste.

Dip each donut in the glaze, then flip it over to coat the other side. Lift it out of the glaze and allow the excess to run off, then place it on the cooling rack. I like to use a fork for this process.