Junior Mint Chocolate Mousse

2 Tablespoons baking cocoa
2 Tablespoons milk
2 Tablespoons butter
5 boxes ( 1.6 oz.) Junior Mints
1/2 teaspoon vanilla
1 12 oz. bowl of Cool Whip

Combine cocoa, milk, butter and Jr. Mints over low heat until melter. Cool. Add vanilla and cool whip. Spoon into dessert glasses and chill.