Layered Vegetable Loaf

Combine first layer ingredients; pour into a greased 8-in. x 4-in. x 2-in. loaf pan. Combine second layer ingredients and spread over first layer. Combine third layer ingredients and spread over second layer. Bake at 300 degrees F for 65-75 minutes or until a knife inserted near the center comes out clean. Run a knife around edges to loosen; cool in pan to room temperature. For sauce, melt butter in a small saucepan; blend in flour until smooth. Gradually add milk, onion salt and pepper. Bring to a boil over medium heat; boil and stir for 2 minutes or until thickened. Unmold loaf onto a serving platter; serve with sauce. ');