Green Bean Casserole

1 tablespoon butter or canola margarine
1 cup fat free or light sour cream
2 tablespoons WONDRA quick-mixing flour (regular flour can also be used)
1 teaspoon salt
1 teaspoon granulated sugar
1/2 cup chopped onion
16 ounce bag of frozen French style green beans (if you want to use canned, use 3 cans, 14.5-ounces each, drained)
1 cup shredded reduced fat cheddar cheese
1/2 cup crumbled Reduced Fat Ritz crackers (or similar), about 10 crackers
canola cooking spray

1. Preheat oven to 350-degrees. Coat a 9 x 9-inch baking dish with canola cooking spray.
2. Melt 1 tablespoon of butter in 2 cup glass measure in microwave. Stir in 2 tablespoons of the sour cream and the flour. Add remaining sour cream, salt, and sugar, and stir until well blended.
3. In large bowl, blend the sour cream mixture with the green beans and half of the cheddar cheese and spread mixture into prepared baking dish.
4. Spread remaining cheese over the top and top that with the cracker crumbs. Spray the cracker topping lightly with canola cooking spray.
5. Bake for 30-35 minutes or until the top is golden and sauce is bubbly.