1. Coarsely chop cabbage and place in a 2-3 quart casserole dish.
2. Chop up the onion and place on top of the cabbage.
3. Melt 1/2 stick of margarine and pour over the cabbage.
4. Sprinkle all with salt and pepper to taste.
5. In a small bowl mix up the soup and mayonnaise.
6. Spread soup & mayo over the top of the cabbage mixture.
7. Preheat oven to 350 degrees.
8. To make the topping, melt the remaining bit of margarine and mix it in with the grated cheese and crushed Ritz crackers.
9. Sprinkle cracker mixture on top of the casserole.
10. Bake for approximately 45 minutes or until the top is brown and the inside is bubbly.
