2 cups all-purpose flour
3/4 cup sugar
1 tablespoon baking powder
1/2 teaspoon ground cinnamon
1/2 teaspoon salt
3/4 cup milk
1/4 cup lemon juice
1 egg
1/4 cup vegetable oil
1 cup fresh or frozen blueberries

In a large bowl, combine flour, sugar, baking powder, cinnamon and salt. In a small bowl, mix the milk and lemon juice. Add egg and oil; mix well. Stir into the flour mixture just until moistened. Fold in the blueberries.

Fill greased or paper-lined muffin cups 2/3 full. Bake at 400 degrees for 20 minutes or until toothpick inserted near center comes out clean.