Melt margarine in a non-stick skillet over medium heat. Add finely chopped bell pepper; cook about 5 minutes over medium low heat. Add eggs, beaten slightly (with a teaspoon of water and a dash of cumin if desired), and season to taste with salt and pepper. Cook stirring often, for a few minutes until eggs begin to set. Push eggs to one side of the skillet and add refried beans to heat together during the final few minutes of cooking.