Preheat the oven to 375°F (190°C). Line a 12-cup muffin tin with paper liners or grease each cup thoroughly.
In a large bowl, whisk together flour, sugar, baking powder, and salt.
In a separate bowl, beat the eggs. Add in the milk, melted butter, and vanilla extract and whisk until combined.
Pour the wet ingredients into the dry ingredients. Stir until just combined, being careful not to overmix.
Gently fold in the blueberries and lemon zest.
Spoon the batter into the prepared muffin cups, filling each about three-quarters full.
Bake for 18-20 minutes or until a toothpick inserted into the center of a muffin comes out clean.
Allow the muffins to cool in the tin for 5 minutes before transferring to a wire rack to cool completely.
Notes
You can store these muffins at room temperature in an airtight container for up to 3 days. For an extra treat, serve warm with a bit of honey or cream cheese.