Step 1

Preheat oven to 400° F. Spray standard muffin tin with non-stick spray, or use baking cup liners, and set aside.

Step 2

For the blueberry muffins: In a small bowl, mix the egg, milk, and oil.

Step 3

In a large bowl, whisk the flour, sugar, baking powder, salt, and cinnamon.

Step 4

Add wet ingredients to dry ingredients and stir. Do not over mix.

Step 5

Fold in blueberries. Batter will be very thick. Spoon into muffin tin and let rest a few minutes while you prepare the crumble topping. For plumper, fuller muffins, divide batter between just 10 of the muffin cups (as shown in my photos). For smaller muffins, use all 12 cups.

Step 6

For the crumb topping: In a small bowl, combine all topping ingredients with a fork, until crumbly. Be sure to have some larger pea-size pieces of crumble. Sprinkle over muffin batter.

Step 7

Bake until crumb topping is a bit golden and a toothpick comes out just barely clean, about 20 minutes. Let rest in pan for about 5 minutes before removing to a cooling rack to cool.