Step 1: Preheat your oven to 375°F (190°C) and prepare a baking sheet by lining it with parchment paper or greasing it lightly.

Step 2: In a large mixing bowl, combine the all-purpose flour, granulated sugar, baking powder, salt, and ground cinnamon. Whisk together until the dry ingredients are evenly distributed.

Step 3: In another bowl, whisk together the eggs, milk, vanilla extract, and melted butter until smooth. Make sure the butter is slightly cooled before adding it to avoid cooking the eggs.

Step 4: Gradually add the wet ingredients into the dry ingredients, stirring gently with a spatula or wooden spoon until just combined. Be careful not to overmix the batter.

Step 5: Gently fold in the diced apples, making sure they are evenly distributed throughout the batter.

Step 6: Using a spoon or a cookie scoop, drop small mounds of the batter onto the prepared baking sheet, spacing them about 2 inches apart. You can slightly flatten the tops with the back of the spoon to create a fritter shape.

Step 7: Place the baking sheet in the preheated oven and bake the fritters for 12-15 minutes, or until they are golden brown on the edges and a toothpick inserted in the center comes out clean.

Step 8: While the fritters are baking, you can prepare an optional glaze by mixing powdered sugar with a small amount of milk or water until smooth. Once the fritters are done baking, let them cool for 5-10 minutes, then drizzle the glaze over the top or dust them lightly with powdered sugar.