Stain Glass Chocolate Fudge

1 (12oz) package semi-sweet chocolate chips
2 tbsp butter or margarine
1 (14oz) can sweetened condensed milk (not evaporated milk)
2 cups dry roasted peants, walnuts or pecans (optional)
1 (10 l/2 oz) package miniature colored marshmallows

In a l quart microwave safe bowl combine chips, margarine and milk. Cook on 100% power (high) for 3 minutes stirring after l l/2 min. Stir to melt chips
Let stand 5 min. (when you let it stand to cool a little it doesn't melt the marshmallows when you add them)

In a large bowl combine nuts and marshmallows. Fold in chocolate mixture
Spread in Wax paper lined 13X9 pan. Chill 2 hrs or until firm.

Remove from pan; peel off paper and cut into squares. Store covered loosely at room temp.