Peanut Butter Fudge

This is another of my "must-make"s for Christmas. Since I had plenty of extra sweets in the freezer, I put together a tray of cookies and fudge to take to a small New Year's gathering (picture below), and the fudge was the only thing that completely disappeared. And it's so easy to make! The one thing I can't remember from year to year is whether the M&Ms on top are chopped in half or kept whole. It tastes good either way though!

Peanut Butter Fudge

2/3 c butter
2/3 c peanut butter
6 cups powdered sugar
1/3 cup milk
1 tbsp vanilla
3/4 cup red and green M&Ms, divided (at least 1/2 cup chopped)

Measure butter and peanut butter into large microwaveable bowl. Microwave until butter melts (1 1/2 - 2 minutes). Stir until blended.
Stir in powdered sugar, milk and vanilla until smooth. Microwave until softened but not bubbly (1 - 1 1/2 minutes). Stir. Quickly stir in 1/2 cup chopped M&Ms.
Pour into buttered 9x9 pan. Sprinkle remaining 1/4 cup M&Ms on top, press in lightly. Refrigerate, covered, at least 1 hour before cutting. Store in refrigerator.
(Chocolate chips can be substituted for M&Ms).
*I'm not sure of the source of this recipe...I got it from my mom who's made it for years.