4.6 from 75 votes
Triple Peanut Butter Monster Cookie Bars
Triple Peanut Butter Monster Cookie Bars combine melted butter, peanut butter, brown sugar, and vanilla with all-purpose flour, then fold in peanut butter M&Ms, semi-sweet chocolate chips, peanut butter chips, and toffee bits. Baked until set but moist, the bars have a rich peanut butter flavor balanced by multiple chocolate and toffee textures, creating a dense and satisfying sweet treat.
Prep Time
5 mins
Cook Time
25 mins
Total Time
30 mins
Servings:
12
generous squares
Calories:
522 kcal
Course:
Baked Goods
Ingredients
- ½ cup butter 1 stick, melted, unsalted
- 1 egg large
- 1 cup light brown sugar packed
- 1 tablespoon vanilla extract
- peanut butter use Jif, Skippy, etc.; don’t use homemade or natural - too runny, heaping 1/2 cup, creamy
- 1 cup all-purpose flour
- 1 cup peanut butter M&Ms
- ¾ cup semi-sweet chocolate chips or a combination, or chunks
- ½ cup peanut butter chips Reese’s brand
- ⅓ cup Heath bar toffee bits
Instructions
- Preheat oven to 350F. Line an 8-by-8-inch baking pan with aluminum foil, spray with cooking spray; set aside.
- In a large, microwave-safe bowl melt the butter, about 1 minute on high power.
- Wait momentarily before adding the egg so you don’t scramble it. Add the egg, brown sugar, vanilla, and whisk until smooth.
- Add the peanut butter and whisk or stir until smooth and incorporated.
- Add the flour and stir until just combined, don’t overmix.
- Add all remaining add-ins and fold to incorporate.
- Turn batter out into prepared pan, smoothing the top lightly with a spatula. I like to strategically place a few M&Ms on the top of the batter for a nice visual effect.
- Bake for about 25 minutes, or until top is set. A toothpick inserted in the center should come out clean, or with a few moist crumbs, but no batter. Allow bars to cool in pan for at least 30 minutes before slicing and serving. Bars will keep airtight at room temperature for up to 1 week, or in the freezer for up to 6 months.
Cup of Yum
Nutrition Information
Serving
1
Calories
522kcal
(26%)
Carbohydrates
39g
(13%)
Protein
7g
(14%)
Fat
39g
(60%)
Saturated Fat
20g
(100%)
Polyunsaturated Fat
16g
(94%)
Trans Fat
1g
(50%)
Cholesterol
83mg
(28%)
Sodium
245mg
(10%)
Fiber
2g
(8%)
Sugar
26g
(52%)
Nutrition Facts
Serving: 12 generous squares
Amount Per Serving
Calories 522
% Daily Value*
| Serving | 1 | |
| Calories | 522kcal | 26% |
| Carbohydrates | 39g | 13% |
| Protein | 7g | 14% |
| Fat | 39g | 60% |
| Saturated Fat | 20g | 100% |
| Polyunsaturated Fat | 16g | 94% |
| Trans Fat | 1g | 50% |
| Cholesterol | 83mg | 28% |
| Sodium | 245mg | 10% |
| Fiber | 2g | 8% |
| Sugar | 26g | 52% |
* Percent Daily Values are based on a 2,000 calorie diet.