Prepare 1 (16 ounce) bag Birdseye broccoli, carrots & cauliflower as directed. Drain and place on bottom of 9 x 9-inch baking dish. Melt 1 stick butter; pour 1/2 over vegetables. Sprinkle at least 1/4 pound grated Velveeta cheese over vegetables. Crumble 1 roll Ritz crackers; sprinkle over cheese. Pour remaining butter over crackers. Bake at 350 degrees for 20 minutes.