Preheat oven to 350 degrees F. In a medium bowl, whisk together all-purpose flour, cornmeal, salt, and baking powder.
In a large bowl, use a hand mixer to cream together butter and sugars until the mixture is light and fluffy. Then beat in one egg at a time followed by vanilla extract.
Stir in dry ingredients until just combined.
Lightly butter a large 2 1/2 qt. baking dish (or an 8×8 baking dish). Spread batter into dish evenly. Dot evenly with raspberries.
Bake the buckle at 350 degrees For 45-50 minutes until the center is set and the edges are browned.
Let cool for 15 minutes, then dust heavily with powdered sugar and serve while warm.