Banana Blueberry Muffins with Cinnamon Crumb

Steps

1. Preheat the oven to 375°F (190°C) and line a 12-cup muffin pan with paper liners.
2. Make the crumb topping first: in a small bowl, stir the melted butter with 40 g of the flour (about one-seventh of it), 40 g of the brown sugar (about two-sevenths of it) and half of the cinnamon until clumpy. Set aside.
3. In a medium bowl, whisk the remaining flour with the baking soda, baking powder, salt and the remaining half of the cinnamon.
4. In a large bowl, mash the banana, then whisk in the remaining brown sugar, the eggs, Greek yogurt, canola oil and vanilla until smooth.
5. Toss the blueberries with 1 spoonful of the flour mixture from the medium bowl so they don't sink.
6. Add the rest of the flour mixture to the banana mixture and fold just until no dry streaks remain; fold in the coated blueberries along with that spoonful of flour mixture.
7. Divide the batter among the 12 liners and sprinkle the crumb topping evenly over each.
8. Bake 20 to 23 minutes, until the tops are golden and a toothpick in the center comes out clean.
9. Cool in the pan for 5 minutes, then move the muffins to a rack to cool for at least 20 minutes before serving.