Super-Easy Rocky Road Fudge

1. LINE 13x9-inch baking pan with foil; grease lightly.
2. MICROWAVE morsels and sweetened condensed milk in large, microwave-safe bowl on HIGH (100%) power for 1 minute; stir.
3. Microwave at additional 10- to 20-second intervals, stirring until smooth.
4. Stiri in vanilla extract.
5. Foldi in marshmallows and nuts.
6. PRESS mixture into prepared baking pan. Refrigerate until ready to serve.
7. Lift from pan; remove foil.
8. Cut into pieces.