Preheat oven to 400 degrees. Prepare a muffin pan with cupcake liners. In a large bowl, sift together 2 cups flour, 1 cup sugar, baking powder, and 1/2 teaspoon salt. Set aside.
In a medium bowl, whisk eggs until smooth. Add the 1/2 cup melted butter, milk, and vanilla, and whisk until combined. Add egg mixture to flour mixture and stir until combined. (Dough will be lumpy.) Fold in raspberries.
To prepare the streusel topping, in a medium bowl combine 1/4 cup flour, 2 tablespoons brown sugar, 2 tablespoons granulated sugar, cinnamon, and 1/8 teaspoon salt. Using a pastry cutter, cut in butter until topping is crumbly and coarse.
Fill prepared muffin cups with batter. Top each muffin with streusel topping, about 1 tablespoon each. Bake until muffin centers bounce back when lightly pressed, about 18 to 22 minutes. Cool muffins on a rack for several minutes before removing from pan. Cool completely and store in an airtight container, up to 4 days.
Notes
Raspberries: Wash, drain, and pick over your berries before using. That means remove any straggler stems, toss any wrinkly or damaged berries, and cut down any large berries. You can also use frozen raspberries.
Yield: My muffin recipe creates 12 regular-sized muffins.
Storage: Store leftovers covered at room temperature for up to 4 days.