Preheat your oven to 375°F (190°C) and line a muffin tin with paper liners.
In a large bowl, whisk together the flour, sugar, baking powder, baking soda, and salt.
In another bowl, beat the egg, then stir in the buttermilk, oil, and lemon zest.
Pour the wet ingredients into the dry ingredients and mix gently until just combined.
Fold in the blueberries carefully to avoid breaking them.
Divide the batter evenly among the muffin cups, filling each about 2/3 full.
Bake in the preheated oven for 18-20 minutes or until a toothpick comes out clean.
Let the muffins cool in the pan for 5 minutes before transferring to a wire rack.
Enjoy warm or at room temperature!
Store any leftovers in an airtight container.