Blueberry Banana Crumb Bread

I have this bad habit. Ever since I made these Apple Crumb Muffins I can't help but put a crumb topping on every type of muffin or bread that I make. It just transforms the ordinary into the extraordinary and I find myself licking every last crumb off the plate. Literally. It's kind of embarrassing when you get caught doing it.  I love banana bread and I also love blueberries and for the life of me I can't remember where I got this recipe. I think maybe it was a combination of a banana bread recipe and a blueberry bread recipe? I don't know, but what I do know is that this bread is so moist and delicious, I guarantee that I won't be the only one licking my plate clean.

3/4 cup buttermilk
3/4 cup packed light brown sugar
1/4 cup butter, softened
2 large eggs
3 medim mashed ripe bananas
1 1/4 cups whole-wheat flour
1 cup all-purpose flour
1 1/2 teaspoons baking powder
3/4 teaspoon ground cinnamon
1/2 teaspoon baking soda
1/2 teaspoon salt
1/4 teaspoon ground nutmeg
1 1/4 cups blueberries, fresh or frozen
Crumb topping:
2/3 cup packed brown sugar
4 tablespoons all-purpose flour
1 teaspoon ground cinnamon
4 tablespoon butter, room temperature

Preheat oven to 350°F. Coat one large loaf pan or 4 small loaf pans with cooking spray. Whisk buttermilk, brown sugar, butter and eggs in a large bowl. Stir in mashed bananas. In a separate bowl, sift together whole-wheat flour, all-purpose flour, baking powder, cinnamon, baking soda, salt and nutmeg. Mix the dry ingredients into the wet ingredients and stir until just combined. Fold in blueberries. Transfer the batter to the prepared pan(s). Mix crumb topping ingredients together then sprinkle on top. Bake about 60-65 minutes for a large loaf, and 30 minutes for the smaller loaves, or until a toothpick comes out clean. Cool in the pan for 10 minutes, then turn out onto a wire rack. Let cool before slicing.

*Source: Unknown