Prep the apples: Peel and chop the apples into small, even pieces. Toss with lemon juice to prevent browning and keep them bright.
Heat the oil: Pour 1 1/2–2 inches of oil into a heavy pot or deep skillet.
Heat to 350–365°F (175–185°C). Keep a thermometer in the oil for consistent frying.
Mix dry ingredients: In a large bowl, whisk flour, sugar, baking powder, baking soda, salt, cinnamon, and nutmeg.
Combine wet ingredients: In another bowl, whisk the eggs, milk, vanilla, and sourdough starter until smooth.
Make the batter: Pour the wet mixture into the dry. Stir gently until just combined.
The batter should be thick but spoonable. If it’s too stiff, add 1 tablespoon of milk at a time.
Fold in apples: Add the chopped apples and any juices. Stir until evenly distributed without overmixing.
Test fry: Drop a teaspoon of batter into the oil to test heat.
It should sizzle right away and turn golden in about 2 minutes.
Fry the fritters: Using a cookie scoop or two spoons, drop 2–3 tablespoon portions into the oil. Don’t crowd the pan. Gently nudge edges to keep a rough, craggy shape for maximum crispness.
Cook and flip: Fry 2–3 minutes per side until deep golden brown.
Keep oil near 360°F; adjust heat as needed.
Drain: Transfer to a wire rack set over a sheet pan. Let excess oil drip off. Repeat with remaining batter.
Make the glaze: Whisk powdered sugar, milk, vanilla, and a pinch of salt until smooth and pourable.
Add a splash more milk if needed.
Glaze while warm: Dip each warm fritter in glaze or spoon it over the tops. Let set for a few minutes. For extra crunch, dust with cinnamon sugar after glazing.
Serve: Enjoy warm.
The texture is best within the first few hours.