Step 1

In a large mixing bowl, beat together brown sugar, granulated sugar, butter, and peanut butter with an electric mixer at medium speed until well mixed and fluffy.

Step 2

Add eggs and vanilla; continue to beat until well combined.

Step 3

In a smaller bowl, combine flour, baking soda, and salt. Add to peanut butter mixture and mix until just combined.

Step 4

Add quick oats and mix until just combined.

Step 5

By hand, stir in chocolate chips and M&Ms.

Step 6

Drop dough by 3 tablespoon scoops onto a baking sheet, scooping only 8 cookies to a sheet (because these cookies are big) and spacing the cookies apart. Use your hand or the bottom of a drinking glass to flatten each dough ball into a patty.

Step 7

Place additional chocolate chips and M&Ms on the top of each dough patty.

Step 8

Bake at 350℉ for 10-11 minutes until set and light golden brown. Allow to cool on pan for 3 minutes, then remove to a rack to cool completely.

Step 9

Use regular creamy peanut butter, not crunchy or natural peanut butter. Crunchy and natural peanut butter are drier than creamy, and will therefore make dry cookies. (I use JIF creamy peanut butter.)

Step 10

Be sure to scoop these cookies large -- a full 3 tablespoons of dough per cookie (a cookie scoop makes this step extra easy). Scooping Monster Cookies large creates a nice-sized, nice-thickness, soft and tender cookie.

Step 11

Placing additional chocolate chips and M&Ms on the top of each dough patty before baking is key to get that characteristic colorful and extra-loaded Monster Cookie top. Press the chocolate chips and M&Ms just slightly into the dough to embed them on the top of the cookie.

Step 12

Do not over bake, as the Monster Cookies will turn rock hard. Bake for just 10-11 minutes only, no more. I always bake mine on the 10 minute end.

Step 13

Once baked, allow the cookies to cool on the pan for 3 minutes before removing them to a rack to cool completely. They are prone to cracking and crumbling if you try to move them off the baking pan too soon.

Step 14

As a side note, 3/4 cup M&Ms is about 9 Halloween fun size packs, if you happen to be using up extra Halloween candy to make these!