Melt the butter in a saucepan over medium heat.
Add the brown sugar, white sugar, and heavy cream.
Stir continuously and let the mixture boil for 5 minutes.
Remove from heat and pour into 2 cups of powdered sugar.
Add 1 teaspoon of vanilla and mix together.
Stir in 1 cup of roughly chopped pecans.
Pour the mixture into a buttered 8x8 dish.
Let cool completely before serving.
