PREHEAT oven to 350 F.
In a large mixing bowl, COMBINE flour, baking powder and sugar.
ADD milk, butter, egg and vanilla; BEAT on low speed until combined; BEAT on medium speed for one minute.
In a small bowl, TOSS berries with one tablespoon flour; FOLD berries into batter.
BUTTER a 13" x 9" baking pan; POUR batter into pan.
BAKE at 350F until done (check with toothpick), about 30 minutes.
FROST with Butter Frosting.
Per Serving (excluding unknown items): 215 Calories; 6g Fat (26.9% calories from fat); 4g Protein; 36g Carbohydrate; 1g Dietary Fiber; 34mg Cholesterol; 191mg Sodium. Exchanges: 1 Grain(Starch); 0 Lean Meat; 0 Fruit; 0 Non-Fat Milk; 1 Fat; 1 Other Carbohydrates.