Preheat the oven to 325 degrees F.

In a large stand mixer bowl with the paddle attachment, cream the softened butter and peanut butter together.

Add the brown sugar and white sugar and mix until fully blended.

Add eggs, one at a time and mix until fully incorporated.

In a medium bowl, add the flour, baking soda and salt. Whisky the dry ingredients until combined. Add the flour mixture into the wet ingredients and mix until just combined.

Fold in the plain chocolate m&m's.

​On a baking sheet, place a parchement paper, or a slipmat on the baking sheet.

With a cookie scoop, scoop out 12 cookie dough balls. Then dip the tops of the cookies into a small bowl or mini m&m's. Place the dipped cookie dough balls back on the baking sheet.

Bake the cookies in a 325 degree F oven for 12 - 15 minutes, or until the bottoms start to turn a golden brown. Allow cookies to cool a bit when you first take out the cookie sheet. After about five minutes you can transfer the cookies to a wire rack to cool.

Once the cookies are completely cooled, store them in an airtight container. If you are interested in keeping some cookies for later, place the cooled cookies in a freezer bag and place them in your freezer. Fresh cookies will keep for four days or in the freezer for up to three months.