Preheat oven to 350F. Line a loaf pan with parchment paper and set aside.
Whisk together the dry ingredients for the crumble topping then add the wet and mix until you have a wet sand texture that clumps together when pinched. Set aside.
Whisk together the dry ingredients in a medium bowl.
In a large bowl, beat together the wet ingredients in a stand mixer or with a hand mixer until well combined.
Add the flour mixture to the wet ingredients and mix on low speed until just combined and a few flour streaks remain.
Toss 1 cup of blueberries in 1 tablespoon flour. Fold in the blueberries with a rubber spatula.
Pour the batter into the prepared loaf pan then sprinkle remaining ½ cup blueberries over the batter.
Crumble the streusel topping evenly over the top of the loaf.
Bake for 40-45 minutes, until golden brown and a toothpick comes out clean with a few crumbs on it.
Let cool on a cooling rack to room temperature before slicing.