Preheat the oven to 400°F (200°C). Line a 12-cup muffin tin with paper liners or grease the cups.
In a large bowl, whisk together 2 cups flour, sugar, salt, and baking powder.
In a separate medium bowl, combine vegetable oil, egg, milk, and vanilla extract. Whisk until smooth.
Pour the wet ingredients into the dry ingredients and stir gently until just combined. Do not overmix; the batter should be slightly lumpy.
In a small bowl, toss the blueberries with 2 tablespoons of flour to coat them. This helps prevent them from sinking to the bottom.
Fold the floured blueberries gently into the batter.
Divide the batter evenly among the 12 muffin cups, filling each about 3/4 full.
Bake for 18 to 20 minutes, or until a toothpick inserted into the center of a muffin comes out clean.
Remove from the oven and let the muffins cool in the pan for 5 minutes, then transfer to a wire rack to cool completely.