These are, oh my! SO GOOD! Monster Cookies are known mainly for their oatmeal, peanut butter, M & Ms, and chocolate chips for extra chocolaty goodness. I enjoy them as Monster Cookie Bars more than I do as a cookie!
These cookie bars are unique in that they use oil instead of butter. I believe this is a big reason why they are so soft and chewy, moist and crumbly.

These Monster Cookie Bars can be baked and then frozen up to 3 months for any upcoming event. You can switch out flavors and M&M colors to match your event and taste buds.
This recipe uses peanut butter chips instead of peanut butter from a jar and can I just mention….. I love peanut butter chips!?! No fumbling around with the peanut butter jar and spatula. No wrestling the sticky peanut butter out of the measuring cup either. Phew!

How to make Monster Cookie Bars
This recipe was inspired by one of my favorite chocolate chip oatmeal bar recipes. The add-ins have been adjusted and the vanilla increased. The dry ingredients include flour, white & brown sugar, baking soda, baking powder, salt, rice krispies, oatmeal, peanut butter chips, chocolate chips, and M&M’s.

The wet ingredients are vanilla, eggs, and canola oil.

The wet and dry ingredients are combined separately and then together.

Pour into a greased 9×13 cake pan and pat down gently. Bake for about 20 minutes or until the edges have lightly browned. The pan is greased and because these bars are made with oil they come out of the pan easily.
If making for an event, you can set aside about 1/4 cup of the M&Ms (or whatever candies you chose) to put on top of the bars before baking. This will ensure plenty of the color is showing on top of the bars.


Change the Flavors
- Swap out chocolate chips for more peanut butter chips
- Use white chocolate chips or milk chocolate chips instead of semi-sweet
- Butterscotch chips
- Reeces pieces M&Ms
- Candy such as crushed heath bars, Reece’s peanut butter cups, or eyeball candies
- Crushed pretzels
- raisins
- nuts

Change the Colors
- Fall & Halloween – peanut butter Reece’s pieces M&M’s, candy eyeballs, candy corn
- Valentine’s Day – red, pink and white M&M’s, Cinnamon Imperials, Valentine sprinkles
- Christmas – green and red M&M’s, white chocolate chips, Christmas sprinkles
- Fourth of July – red, white, and blue M&M’s, Patriotic sprinkles
- Sports – M&M’s and/or sprinkles that coordinate with your favorite sports team
- Graduation School Colors – M&M’s and/or sprinkles that coordinate with your school colors
- Birthday Parties – M&M’s or candies that reflect the person’s favorite colors and/or flavors
If you can’t find the exact M&M colors you want at the store and you don’t mind spending extra……you can visit M&M’s website HERE to order any specific colors you may need for your event. I do not make a profit off of the M&M link.
Here are more scrumptious bar recipes to try….
Easy to Make – Applesauce Bars – with Vanilla Icing
Easy Buckeye Brownies Recipe (peanut butter brownie)

Best Monster Cookie Bars (without butter)
Ingredients
- 2 cups flour
- ½ cup white sugar
- 1 cup brown sugar gently packed
- 1 tsp baking soda
- 1 tsp baking powder
- 1 tsp salt
- 1 1/2 cups quick cook oatmeal
- 1 cup rice krispies
- 1/2 cup chocolate chips
- ¾ cup peanut butter chip
- ¾ cup M & M candies
- 1 cup oil I use Canola oil
- 2 eggs
- 1 tbls vanilla
Instructions
- Preheat the oven to 350 degrees. Grease a 9 x 13 cake pan.
- In a large mixing bowl, stir the dry ingredients together and set aside.
- In a smaller mixing bowl combine the liquid ingredients with a fork (do not beat the eggs, just stir until combined).
- Add the wet ingredients to the dry ingredients and stir until combined.
- Pour into the greased cake pan and pat down gently. Bake for about 20 minutes or until edges are lightly browned.

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