Peel and core the apples, then slice them into 1/4-inch thick rings.
In a bowl, whisk together flour, sugar, baking powder, salt, cinnamon, nutmeg, and ginger. In another bowl, mix egg, milk, and vanilla.
Combine wet and dry ingredients to make a thick batter.
Heat about 1 inch of vegetable oil in a skillet or deep fryer to 350°F (175°C).
Dip each apple ring in the batter, then fry in batches until golden brown and crispy, about 2-3 minutes per side.
Remove from oil and drain on paper towels. While still warm, coat each ring in a cinnamon-sugar mixture.
Serve warm, optionally with caramel sauce, vanilla ice cream, or a dusting of powdered sugar.