Grease bottoms only of 12 medium muffin cups, 2-1/2 X 1-1/4 inches, or paper lined cups.
Beat the milk, oil, vanilla extract and egg.
Stir in the flour, sugar, baking powder & salt all at once until flour is moist (should be lumpy). Add the blueberries, combine and divide batter evenly among muffin cups.
Sprinkle each using about 2 tsp of the prepared topping.