Preheat oven to 400°F (200°C) and line a heavy-gauge baking sheet with parchment paper.
In a large mixing bowl, sift together the all-purpose flour, granulated sugar, baking powder, cinnamon, salt, and nutmeg to ensure even distribution of leavening agents.
In a separate vessel, whisk together the 1/2 cup milk, eggs, melted butter, and 1 teaspoon vanilla extract until emulsified.
Incorporate the wet mixture into the dry ingredients using a folding motion until just combined; avoid over-agitation to prevent gluten development.
Fold the finely diced apples into the batter until evenly distributed.
Dispense 1/4 cup portions of the batter onto the prepared baking sheet, maintaining 2-inch intervals for thermal circulation.
Bake for 12 to 15 minutes until the internal temperature reaches approximately 190°F (88°C) or until a digital probe comes out clean.
While baking, whisk the powdered sugar, 2 tablespoons milk, and 1/2 teaspoon vanilla extract in a small bowl to create the glaze.
Transfer the fritters to a wire cooling rack and drizzle the glaze over the tops while the surface temperature is still warm to facilitate better adhesion.