1/2 cup margarine
1/2 cup white sugar
1/4 cup water
1 cup buttermilk
2 cups powdered brown sugar
6 eggs, lightly beaten
2 (2 ounce) cans lemon-lime flavored carbonated beverage
1 cup hot water
4 ounce container frozen whipped topping, thawed
4 cups pecans, broken red onion not used