Preheat the oven: Set your oven to 375°F and grease a muffin tin or line a baking sheet with parchment paper.
Mix the dry ingredients: In a medium bowl, whisk together the flour, baking powder, cinnamon, and salt.
Prepare the wet ingredients: In a separate large bowl, beat the eggs and sugar together until slightly frothy. Stir in the milk, vanilla, and melted butter.
Combine wet and dry: Add the dry ingredients to the wet ingredients and stir until just combined. Do not overmix.
Add the apples: Gently fold the thin apple slices into the batter. You can layer a few slices on top of each portion for extra visual appeal.
Spoon into the tin: Scoop the batter into prepared muffin wells or form mounds on the lined baking sheet, allowing space between each.
Bake the fritters: Bake for 20–25 minutes, or until puffed and golden around the edges. A toothpick should come out clean when inserted in the center.
Cool slightly: Let the fritters cool in the pan for 5 minutes before transferring to a wire rack.
Dust with powdered sugar: Once warm but not hot, sprinkle with powdered sugar and serve immediately for best texture and flavor.