Praline Ice Cream Sauce

1 1/2 cups golden or light brown sugar, packed
1/2 cup granulated sugar
1 cup buttermilk
1/2 cup unsalted butter
3 Tbsp. light corn syrup
1 tsp. baking soda
1 tsp. vanilla extract
1/2 cup coarsely ground pecans

Combine sugars, buttermilk, butter, syrup, and baking soda, in a heavy saucepan. Bring to the boiling point, then reduce heat and simmer for 10 minutes, stirring occasionally. Remove from the heat and stir in the vanilla and nuts. Cool completely before serving. The sauce will thicken.