3/4 cup butterscotch chips
3/4 cup semisweet chocolate chips
1 cup cocoa powder
1 teaspoon vanilla extract
2 1/4 cups milk
3/4 cup melted butter
In microwave-safe bowl, mix together butterscotch chips and chocolate chips until well blended. Microwave for 1 minute, stirring, then stir in cocoa; mix just until smooth. Stir in vanilla. Stir in milk; beat until mixture is creamy and has no lumps, about 5 minutes.
Using an electric mixer, beat on medium speed until chips and chocolate are melted and mixture thickens. Place milk chocolate lumps in hot milk. Blend on high speed until desired consistency is reached. Spoon into tall glass container. Chill at least overnight. 3/4 cup of chocolate mixture can be refrigerated a day or frozen for 12 days. Remove chocolate mixture to cool completely.