1. Heat oven to 400°. Grease bottoms only of 12 medium muffin cups, 2 1/2 x 1 1/4 inches, with shortening, or line with paper baking cups. 2. Make Streusel Topping (see separate recipe); set aside. 3. Beat milk, oil, and egg in large bowl with fork or wire whisk. Stir in flour, sugar, baking powder and salt all at once just until flour is moistened (batter will be lumpy). Fold in blueberries. Divide batter evenly among muffin cups. Sprinkle each with about 1 tablespoon topping. 4. Bake 20 to 25 minutes or until golden brown. If baked in greased pan, let stand about 5 minutes in pan, then remove from pan to wire rack; if baked in paper baking cups, immediately remove from pan to wire rack. Serve warm if desired.