In a large bowl, whisk flour, sugar, baking powder, cinnamon, nutmeg, and salt together. In a smaller bowl, whisk the egg, vanilla, and milk.
Pour the melted butter into the flour mixture and stir until small crumbs form. Next, add the egg mixture, sourdough discard into the flour mixture, and lastly, fold in the blueberries.
Place dough on a heavily floured surface and sprinkle the tops before rolling out. The dough will be soft, but it shouldn't be very sticky.
Using a donut cutter, cut out the donuts.
Fold the extra dough, gently bringing it in a ball to roll out again. Try not to overwork the dough. Heat the vegetable or canola oil in a dutch oven or large enough pot to fry two to three donuts at a time.
Test the oil temperature with a donut hole first. The donut hole should sink, then float within ten seconds. Fry donuts and drain on a wire rack, preferably over a baking sheet.
Once the donuts touch the hot oil, they will expand and become fluffy.
Be careful to not overmix the dough.
Feel free to make doughnut holes instead of donuts.
Coat these sourdough donuts with a chocolate glaze for extra flavors.
Substitute with any freshly cut fruit such as strawberries or apples.
Lightly dust these donuts with powdered sugar once they have cooled off.
A freshly fed starter will allow the donuts to have a much milder taste.
Store the leftovers in an airtight container for up to four days.
You can use a deep fryer if you have one on hand.
These donuts are perfect for baked cake donuts as well. Perfect with a nice cup of coffee or hot cocoa!
Lemon Zest: Add lemon zest for a classic combination of citrus and berry. Add in a tablespoon of lemon zest to the batter for a fresh and glorious combination.
Cinnamon Sugar: Looking for something other than glazed donuts, try dipping the warm donuts in a combination of cinnamon and sugar. Use three parts sugar to one part cinnamon on a plate. Next, lay the donut on top and repeat until you have coated the tops of each donut.