These raspberry-dark chocolate chip muffins have large, overflowing tops, just like the ones from your favorite bakery! [br][br]You can find oat flour in the natural section of your grocery store, but I made my own by processing old fashioned oats in the food processor. A heaping cups of oats yielded enough flour – with a little to spare. [br][br]I like to use fresh berries, but frozen will work just as well. You can also save yourself about 50 calories by skipping the streusel topping, but I like the little bit of extra sweetness that it provides.
Preheat oven to 400*F. Line a 12-cup muffin tin with paper liners; grease the top of the tin with a little oil or butter.
In a large mixing bowl, sift together the flours, baking powder, baking soda, and salt. In a second bowl, whisk together the sugar, yogurt, melted butter, eggs, and vanilla. Pour the wet ingredients into the dry ones; mix until just incorporated – do not overmix, the batter will be very thick. Fold in the berries and chocolate chips.
Divide the batter between the prepared muffin cups (the batter will mound above the rim of the pan.) In a small bowl, use a fork to mix together 1/4 cup flour, 1/4 cup butter, and 2 tablespoons brown sugar until crumble. Crumble the topping over each muffin.
Bake for 20-25 minutes, or until the tops are golden brown and springy. Allow muffins to cool at least 15 minutes before removing them from the pan.