To Die For Blueberry Muffins

To Die For Blueberry Muffins (from KC Stake Relief Society Cookbook.) These really are the best recipe I have ever tried.

1 1/2 cups all-purpose flour
3/4 cup white sugar
1/2 teaspoon salt
2 teaspoons baking powder
1/3 cup vegetable oil
1 egg
1/3 cup milk
1 cup blueberries (I often use frozen)
1/2 cup white sugar
1/3 cup all-purpose flour
1/4 cup butter, cubed
1 1/2 teaspoons ground cinnamon

Preparation of To Die For Blueberry Muffins
Preheat oven to 400 degrees F. Grease muffin cups or line with muffin liners.
Combine 1 1/2 cups flour, 3/4 cup sugar, salt and baking powder.
Place vegetable oil into a 1 cup measuring cup; add the egg and enough milk to fill the cup. Mix this with flour mixture. Fold in blueberries. Fill muffin cups right to the top, and sprinkle with crumb topping mixture.

To Make Crumb Topping: Mix together 1/2 cup sugar, 1/3 cup flour, 1/4 cup butter, and 1 1/2 teaspoons cinnamon. Mix with fork, and sprinkle over muffins before baking.

Bake for 20ish minutes.
My friend Tiffany gave me a fantastic tip for the butter in the topping: grate it with a cheese grater. Super easy.