Butter 12 (2 1/2-inch) ramekins or small bowls. Combine all of the appetizer ingredients. Press the mixture into the prepared ramekins, leaving a hollow in the middle of each ramekin. Bake until the edges begin to brown, about 15 minutes.
In saucepan over low heat, combine margarine and flour. When blended, add all remaining ingredients except lemon juice and vegetables. Cook until bubbly. Add lemon juice. Into center of each ramekin, place a tablespoon of vegetables. Cover with approximately 2 tablespoons of sauce. Bake for 5 minutes. Garnish and serve hot.