Sourdough Blueberry Lemon Fritters

Add the active sourdough starter, warm milk, flour, eggs, salt, sugar, and vanilla extract to the bowl of a stand mixer fitted with the dough hook attachment.
Mix on low to medium speed until a shaggy dough forms.
With the mixer running, add the softened butter one tablespoon at a time, allowing each addition to incorporate before adding the next. Scrape down the sides of the bowl as needed.
Increase the mixer speed to high and knead for 7-10 minutes, or until the dough pulls away from the sides of the bowl and clings to the dough hook.
The dough will be very soft and sticky. Brioche dough is known for being wetter than many bread doughs, so resist the urge to add additional flour. The dough will become smoother and easier to work with after fermentation.
Cover the bowl and allow the dough to bulk ferment at room temperature for 6-10 hours, or until it has risen by approximately 30-50%.
Note: Brioche dough rises slowly due to the eggs, butter, and sugar. In a cooler home around 68°F (20°C), fermentation may take closer to 10 hours. Watch the dough rather than the clock.

In a small bowl, combine the chopped blueberries, granulated sugar, and lemon zest. Stir until evenly combined and set aside.

Turn the fermented dough onto a lightly floured work surface and roll it into a large rectangle approximately ¼-inch thick.
Evenly distribute the blueberry filling over the surface of the dough.
Starting with the long edge, roll the dough tightly into a log just as you would for cinnamon rolls.
Using a bench scraper or sharp knife, cut the log lengthwise down the center. Then continue cutting both directions repeatedly until the dough is divided into small pieces.
Using your hands, gather portions of dough and firmly press them together to form round fritter patties about 3-4 inches in diameter. Be sure to compress the dough pieces very well as you shape them. If the pieces are not firmly pressed together, they may separate while frying.
You should end up with approximately 8 fritters.
Place each fritter onto an individual parchment paper square to make transferring them to the oil easier.

While the oil heats, add the blueberries, powdered sugar, and lemon juice to a blender or food processor.
Blend until smooth.
Pour the glaze through a fine mesh sieve to remove the blueberry skins and seeds, creating a smooth glaze. Set aside.

Heat 2-3 inches of oil in a heavy-bottomed pot or Dutch oven to 350-370°F (177-188°C).
Carefully lower the fritters into the hot oil, working in batches to avoid overcrowding the pan.
Fry for approximately 3-4 minutes per side, or until deeply golden brown and cooked through.
It is important to maintain the oil temperature between 350-370°F throughout frying. If the oil is too hot, the outside will brown before the center has finished cooking. If the oil is too cool, the fritters may absorb excess oil.
Transfer the cooked fritters to a wire rack set over a baking sheet lined with paper towels to catch any excess oil.

While the fritters are still warm, dip both sides of each fritter into the blueberry lemon glaze.
Return the glazed fritters to the wire rack and allow the glaze to set before serving.
Enjoy warm or at room temperature.