In a large bowl, combine the chopped apples, granulated sugar, flour, baking powder, and salt. Mix until the apples are evenly coated with the dry ingredients.
In a separate bowl, whisk together the melted butter, egg, and vanilla extract.
Add the wet ingredients to the dry ingredients and mix until a dough forms.
Cover the dough and refrigerate for at least 30 minutes.
Heat the vegetable oil in a deep frying pan to 375°F (190°C).
Using a cookie scoop or a spoon, drop the dough into the hot oil, making sure not to overcrowd the pan.
Fry the fritters for 2-3 minutes on each side, or until they are golden brown and cooked through.
Remove the fritters from the oil and place them on a paper towel-lined plate to drain excess oil.
Dust the fritters with confectioners' sugar (if desired) and serve warm.