Rocky Mountain Frosting

This particular frosting goes with the Lemon Treasure Cake recipe, which at first seems like an odd combination, but it works really well. I did not have Nana's recipe card for this one and I looked around various websites until I found some common recipes. Below is the result and is tailored to be used with the Lemon Treasure Cake.

ROCKY MOUNTAIN FROSTING

1/2 cup butter                            2 tbsp. all purpose flour
1/2 cup evaporated milk          1/2 cup firmly packed brown sugar
2 cups powdered sugar               1 tsp. vanilla extract
1 c. chopped walnuts

Melt butter in a small saucepan over low heat; stir in flour. 
Add milk and cook until smooth and thickened. 
Remove from heat; add brown sugar and mix well. 
Add powdered sugar and vanilla, mixing well. 
Chop walnuts as needed to ensure they are manageable and mix into frosting.
Cool; spread over cake
Makes enough for top and sides of 1 (10") cake.