In a medium bowl, whisk together flour, sugar, baking powder, cinnamon, and salt. Set aside.
In a separate bowl, beat the egg, then stir in milk and vanilla extract.
Gently fold the wet ingredients into the dry ingredients until just combined, ensuring not to overmix. Stir in the finely diced apple.
Heat vegetable oil in a deep frying pan or dutch oven to 350°F (175°C). Use a thermometer to monitor the temperature.
Carefully drop spoonfuls of the batter into the hot oil, frying a few at a time to avoid overcrowding the pan.
Fry for 2-3 minutes per side, or until the fritter bites are golden brown and cooked through. Remove with a slotted spoon and place on a wire rack lined with paper towels to drain excess oil.
Serving Suggestion
Optionally, you can drizzle with a simple glaze made from powdered sugar and milk while warm.
Notes
Enjoy these apple fritter bites warm for the best flavor. They are best consumed fresh.