3/4 c. half and half
1 tbsp. butter
1 1/2 c. sugar
16 lg. marshmallows, cut in half
1 (12 oz.) pkg. chocolate chips
1 c. chopped nuts
1 tsp. vanilla

Combine butter, milk, sugar and marshmallows in a 2 quart microwave bowl. Microwave 3-4 minutes on high until marshmallows melt. Stir. Microwave again until it boils and sugar is dissolved. Stir in chocolate, nuts, and vanilla. Beat until smooth and well mixed. Spread in a buttered 8 x 8 inch dish.