Directions

1. Butter a baking sheet. Butter the sides of a heavy, 2-quart saucepan.
2. In the saucepan, stir together white sugar, brown sugar, cream, milk and margarine and bring to a boil over medium heat. Heat, without stirring, to between 234 and 240 degrees F (112 to 116 degrees C), or until a small amount of syrup dropped into cold water forms a soft ball that flattens when removed from the water and placed on a flat surface. Remove from heat and cool to lukewarm (110 degrees).
3. Stir in vanilla and beat vigorously until mixture loses its gloss. Quickly stir in pecans and spread on prepared sheet. Score into squares while warm; cut when firm.