Mix the flour, sugar, baking powder, and salt together, whisking to mix.
Mix the egg and milk in a separate bowl, then add it to the dry ingredients and stir until it's barely integrated.
Mix the sugar and cinnamon with the apple pieces, then pour the mixture into the batter, giving it a quick toss to distribute the apples.
Warm up the oil to 370 degrees.
Use a cookie scoop or heaping spoonfuls of the batter, and fry for two to three minutes, or until golden brown, making careful to include apples in each scoop.
When cooking in a sealed fryer, make sure to jiggle the pan occasionally to guarantee uniform cooking. To achieve equal cooking while cooking in an open frying pan or poy, turn the fritters using a spatula or fork.
After taking the fritters out of the fryer, arrange them on a cooling rack that has paper towels underneath to collect any drips. Roll the fritters in sugar and cinnamon as soon as you can manage them. Let them cool a little bit before dusting with powdered sugar or dipping them in a simple glaze.
Whisk together 1 ½ cups powdered sugar, 1-1 ½ TBS milk, and a dash of vanilla to form the glaze. Blend till silky, then pour it over fritters or just dip them in. They don't actually "keep" that way, so after dipping them in, let them settle for a few minutes and then enjoy. Fritters are best eaten warm, just after preparation. Fry in three- or four-piece batches for optimal results. To make it simple to put the batter into the oil, I use a tiny cookie scoop.