Step 1. Prepare the apples. Start by peeling and dicing the apples into small bite-sized cubes. The smaller pieces will cook quickly and blend well into the batter. Set them aside while you mix the dry ingredients.
Step 2. Mix the dry ingredients. In a large bowl, whisk together the flour, sugar, baking powder, cinnamon, nutmeg, and salt. Mixing these first helps distribute the spices evenly throughout the batter.
Step 3. Make the wet mixture. In a separate medium bowl, combine the milk, egg, vanilla, and melted butter. Whisk until smooth and slightly frothy. This will give the fritters a tender and fluffy texture.
Step 4. Combine wet and dry. Pour the wet ingredients into the dry mixture and stir gently until just combined. Do not overmix, as that can make the fritters dense. Fold in the diced apples carefully so they are evenly distributed.
Step 5. Fry the fritters. Heat about 2 inches of oil in a deep skillet or Dutch oven until it reaches 350°F. Drop spoonfuls of the batter into the oil, cooking 2 to 3 fritters at a time. Fry each side for about 2 to 3 minutes until golden brown. Use a slotted spoon to transfer them to a wire rack lined with parchment or paper towels.
Step 6. Glaze the fritters. In a small bowl, whisk together powdered sugar, milk, and vanilla to make a smooth glaze. Dip each warm fritter into the glaze or drizzle it on top. Allow the glaze to set for a few minutes before serving.