My best blueberry muffins

Ingredients
1 1/2 cups flour
3/4 cup sugar
1/2 teaspoon salt
2 teaspoons baking powder
1/3 cup veggie oil
1 egg
1/3 cup milk
1 cup fresh blueberries

Crumb topping:
1/2 cup brown sugar
1/3 cup flour
1/4 cup butter
1 1/2 teaspoon cinnamon

Instructions
Preheat oven to 400 degrees.
Grease muffin cups.
Combine flour, sugar, salt and baking powder. Add oil, egg and milk. Fold in blueberries. Fill cups to the top; sprinkle with crumb topping.
Bake 20-25 minutes.