Preheat oven to 425° and spray a 12-count muffin pan with non-stick cooking spray.
In a medium bowl, whisk together flour, baking powder, and salt.
In a large bowl whisk together the oil, sugars, eggs, vanilla, lemon juice, and milk.
Add the dry ingredients to the wet ingredients.
Pour the batter evenly into the muffin tins, filling close to the top. Top with a heaping tablespoon of fresh or frozen blueberries. (Or fold rinsed and dried fresh or frozen blueberries into the batter before adding to the muffin pan.)
Sprinkle the tops generously with coarse sugar. Bake in the preheated oven for 5 minutes.
With the muffins still in the oven, reduce the temperature to 375° and continue baking for 15-20 minutes, until set and a toothpick comes out clean.