Preheat the Oven: Start by preheating your oven to 375°F (190°C). Line a muffin tin with paper liners for easy removal.

Mix Dry Ingredients: In a large bowl, whisk together the flour, sugar, baking powder, and salt until well combined.

Prepare Wet Ingredients: In another bowl, mix the milk, vegetable oil, egg, lemon juice, and lemon zest. Whisk until smooth.

Combine Mixtures: Pour the wet mixture into the dry ingredients. Stir gently until just combined—be careful not to overmix!

Fold in Blueberries: Gently fold in the blueberries, ensuring they are evenly distributed throughout the batter.

Fill Muffin Cups: Using a spoon or ice cream scoop, fill the muffin cups about 2/3 full with batter.

Bake: Place the muffin tin in the preheated oven and bake for 18-20 minutes, or until a toothpick inserted into the center comes out clean.

Cool: Once baked, let the muffins cool in the pan for 5 minutes before transferring them to a wire rack to cool completely.