Peanut Butter Marshmallow Brownies

These peanut butter marshmallow brownies are a thick brownie topped with peanut butter, gooey marshmallows and a sweet chocolate frosting. They're always a crowd pleaser, and are very easy to whip together.

For more fun brownie recipes, try my biscoff brownies, my rolo brownies or my oreo cheesecake brownies.

• Butter: I love using salted butter in my recipes, but unsalted works fine too.
• Cocoa Powder: You can use unsweetened cocoa powder, dutch process or black cocoa powder for these.
• Peanut Butter: I use crunchy because I love the added texture, but feel free to use creamy.
• Marshmallows: You need to use mini marshmallows for this recipe.

Step by Step Instructions

1. Step 1: In a medium mixing bowl whisk together butter, sugar, eggs and vanilla until light and fluffy.

2. Step 2: Whisk together salt, flour and 3 tablespoons of cocoa powder. Stir into the brownie batter until combined.

3. Step 3: Spread evenly into baking pan. Sprinkle with chocolate chips.

4. Step 4: Bake the brownies for 17-20 minutes, or until done baking.

5. Step 5: As soon as brownies are done baking, warm peanut butter in the microwave for about 15 seconds to melt and make pourable. Spread over freshly baked hot brownies. Top with marshmallows and return to the oven for another 3-5 minutes until puffy. Remove and allow to start cooling.

6. Step 6: While brownies are cooling make the chocolate frosting.
7. In a small glass bowl melt together the butter, cocoa powder and milk in the microwave. I like to do it for about 1 minute or until it's hot enough to dissolve the cocoa powder. Add powdered sugar and salt to a medium mixing bowl, and add the hot butter mixture. Beat until smooth and glossy. Add vanilla and combine. Pour and spread over warm brownies. Allow to completely cool and set up before cutting.

FAQ

Storing & Freezing

Peanut butter marshmallow brownies can be stored in an airtight container, or with saran wrap along the top to keep maximum freshness. They will stay fresh for up to 5 days.

Brownies will freeze well for up to 3 months. Wrap tightly and store in a large freezer bag or container. Enjoy later with a bowl of ice cream!

Other Popular Recipes to Try

Peanut Butter Marshmallow Brownies

Brooke Homec

These peanut butter marshmallow brownies are a thick brownie topped with peanut butter, gooey marshmallows and a sweet chocolate frosting. They're always a crowd pleaser!

5 from 9 votes

Print Recipe Pin Recipe

Prep Time 15 minutes mins

Cook Time 21 minutes mins

cool time 30 minutes mins

Total Time 1 hour hr 6 minutes mins

Course Dessert

Cuisine American

Servings 12

Calories 403 kcal

Bake ModePrevent your screen from going dark

Ingredients

 

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• ▢ ½ cup (113.5 g) salted butter melted
• ▢ 1 cup (200 g) granulated sugar
• ▢ 2 large eggs room temperature
• ▢ 1 teaspoon vanilla
• ▢ ½ teaspoon (0.5 teaspoon) salt
• ▢ 3 tablespoons cocoa powder
• ▢ ¾ cup (100 g) all-purpose flour
• ▢ ¼ cup (45 g) chocolate chips
• ▢ ½ cup (129 g) peanut butter I use crunchy
• ▢ 2 cups (100 g) mini marshmallows
• ▢ ¼ cup (56.75 g) butter
• ▢ 2 tablespoons cocoa powder
• ▢ ¼ cup (59.15 ml) milk
• ▢ 2 cups (240 g) powdered sugar
• ▢ ¼ teaspoon (0.25 teaspoon) salt
• ▢ ½ teaspoon (0.5 teaspoon) vanilla

Instructions

 

• Preheat oven to 350 F. Line an 8x8 baking pan with cooking spray and parchment paper.
• In a medium mixing bowl whisk together butter, sugar, eggs and vanilla until light and fluffy.
• Whisk together salt, flour and 3 tablespoons of cocoa powder. Stir into the brownie batter until combined.
• Spread evenly into baking pan. Sprinkle with chocolate chips.
• Bake the brownies for 17-20 minutes, or until done baking.
• As soon as brownies are done baking, warm peanut butter in the microwave for about 15 seconds to melt and make pourable. Spread over freshly baked hot brownies. Top with marshmallows and return to the oven for another 3-5 minutes until puffy. Remove and allow to start cooling.
• While brownies are cooling make the chocolate frosting.

  In a small glass bowl melt together the butter, cocoa powder and milk in the microwave. I like to do it for about 1 minute or until it's hot enough to dissolve the cocoa powder. Add powdered sugar and salt to a medium mixing bowl, and add the hot butter mixture. Beat until smooth and glossy. Add vanilla and combine. Pour and spread over warm brownies. Allow to completely cool and set up before cutting.

Video

Notes

You can use creamy peanut butter, or any nut butter if you prefer for these. I just like having the texture of the peanuts. You could even skip that part all together if needed.

I have given both cups and grams as measurements. Grams will be more precise, especially when measuring flour. If you don’t have a kitchen scale, no problem! Just lightly spoon flour into your measuring cup to insure its not packed in there. Light and fluffy is the key.

Nutrition

Calories: 403kcalCarbohydrates: 56gProtein: 5gFat: 19gSaturated Fat: 10gPolyunsaturated Fat: 2gMonounsaturated Fat: 6gTrans Fat: 0.5gCholesterol: 62mgSodium: 304mgPotassium: 136mgFiber: 2gSugar: 45gVitamin A: 408IUCalcium: 27mgIron: 1mg

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