Step 1: Preheat oven to 375 degrees F (190 degrees C). Grease or spray 12 muffin cups.
Step 2: In a small bowl, stir together 1/2 cup (120 ml) milk and 2 tablespoons (30 ml) vegetable oil.
Step 3: In a large bowl, mix together 2 cups (250 grams) all-purpose flour, 1/2 cup (100 grams) sugar, 2 teaspoons (10 grams) baking powder, and 1/2 teaspoon (2.5 grams) salt.
Step 4: Add the milk mixture and 1 cup (150 grams) fresh or frozen blueberries to the flour mixture. Stir just until the flour is moistened. Do not overmix.
Step 5: Divide the batter evenly among the prepared muffin cups. Bake for 20 minutes, or until the muffins are golden brown and a toothpick inserted into the center comes out clean.
Step 6: Remove the muffins from the oven and let cool for 5 minutes before serving. Serve warm or at room temperature.