Preheat oven to 425°. Melt 2 tablespoons Country Crock® Spread in large nonstick skillet and saute broccoli and red bell pepper until crisp tender. Whisk milk and flour in large bowl. Add chicken, cooked vegetables, 2 cups cheese, and onion powder; toss to mix. Pour into 8-in. baking dish.
Combine panko crumbs, remaining 1 tablespoon Spread and remaining 1/4 cup cheese in small cup. Sprinkle over top of casserole.
Bake 30 to 35 minutes or until crumbs are golden and mixture is bubbly around edges.