TOPPING:

2 tbsp. butter
2 tbsp. brown sugar
1/4 tsp. cinnamon
1/4 c. walnuts

Melt butter. Remove from heat and add all other ingredients; set aside.

MUFFINS:

1 1/2 c. blueberries (frozen or fresh)
1 1/2 c. flour
2 tsp. baking powder
1/2 stick butter
2/3 c. sugar
1 egg
1 tsp. vanilla
1/3 c. milk

Sift dry ingredients together. Cream butter and sugar until fluffy. Beat in eggs and vanilla. Stir in flour alternately with milk. Fold in blueberries. Fill muffin cups 2/3 full and sprinkle with topping. Bake at 400 degrees for 20 minutes.