Chex Pumpkin Pie Crunch

1/4 cup brown sugar
1 tablespoon pumpkin pie spice
1/4 cup butter
2 teaspoons vanilla
2 cups cinnamon chex cereal
2 cups wheat chex cereal
2 cups honey nut chex cereal
8 oz pecans

Mix brown sugar, pumpkin pie spice. Set aside. Melt butter and add vanilla. In a large bowl, combine cereals and pecans. Pour butter mixture over cereal and stir. Add sugar mixture and evenly coat everything. Microwave on high 5 minutes, stirring every minute. Spread on cookie sheet to dry.