In a bowl combine the 1/2 cup flour, 1/4 brown sugar, 2 tbsp sugar, 1/8 tsp kosher salt, and ¼ cup cold diced butter.

Using your fingers, pinch the butter into the mixture gently until small clumps form and are about the size of a pea. Place in the fridge while you make the muffin batter.

Preheat the oven to 425° F and line a 12 cup muffin tip with muffin liners.

Take out 2 medium sized bowls. In one bowl, add the 2 1/2 cups flour, 1 cup sugar, 2 tsp baking powder, 1/2 tsp baking soda, and 1/2 tsp kosher salt. Mix lightly with a whisk.

Add the dried blackberries on top of the dry ingredients and lightly coat them.

In the second bowl, add the 1/4 cup butter and microwave for 30 seconds at a time until fully melted. Then add in the bananas and mash well with a fork.

Add the 1/4 cup vegetable oil, 1/4 cup greek yogurt, 2 eggs, and 1 tbsp vanilla extract. Mix well with the whisk.

All at once, add the dry ingredients into the wet ingredients. Using a large spatula, lightly and gently fold in the flour taking care not to over mix or mix too hard.

You want the flour to JUST mix in till there are no mare large streaks. The batter will be thick and lumpy.

Using an ice cream scoop for accuracy, scoop the batter into the prepared muffin tin all the way to the top.

Sprinkle the streusel on top of the muffins. Be generous! It’s ok if there’s a lot on the muffin tin.

Bake for 7 minutes on 425, then lower the temperature to 350°F and continue to bake for another 13 minutes.

Take the muffins out and let them cool for 5-10 minutes in the tin, then remove and cool completely on a wire rack.