Mix Dry Ingredients: In a mixing bowl, combine the all-purpose flour, granulated sugar, baking powder, and salt. If you'd like a subtle citrusy flavor, add some lemon zest to the dry mixture and mix well.

Combine Wet Ingredients: In a separate bowl, whisk together the egg, milk, vegetable oil, and vanilla extract until well combined.

Combine Dry and Wet Mixtures: Pour the wet mixture into the dry mixture and stir until just combined. Be careful not to overmix; a few lumps are okay. Overmixing can result in tough muffins.

Add Blueberries: Gently fold in the fresh blueberries into the muffin batter. Be gentle to avoid smashing the blueberries and to distribute them evenly.

Fill Muffin Cups: Divide the muffin batter evenly among the prepared muffin cups, filling each about two-thirds full.

Air Fry: Place the muffin-filled cups in the preheated air fryer basket. You may need to air fry the muffins in batches, depending on the size of your air fryer. Leave some space between the muffin cups to allow for air circulation.

Cool and Serve: Once done, carefully remove the muffins from the air fryer and let them cool in the muffin cups for a few minutes. Then transfer them to a wire rack to cool completely. Enjoy your Homemade Blueberry Muffins!