6-Ingredient Peanut Butter Cookie in a Mug

This single-serve Peanut Butter Cookie in a mug is the perfect size for one or two people! Made with six basic pantry ingredients, this easy on-demand dessert is ready in less than 5 minutes.

The perfect peanut butter cookie for those times your sweet tooth is chatting away but you don’t want to bake a full batch of cookies!

This quick and easy single-serve peanut butter mug cookie requires just 6 basic ingredients: unsalted butter, peanut butter, pure maple syrup, egg yolk, vanilla extract, and gluten-free all-purpose flour. Of course we can mix in some chocolate chips for good fun, but those are entirely optional.

I find this delicious peanut butter cookie turns out with just the right amount of sweetness and plenty of rich peanut butter flavor.

Feel like more of a cake consistency than a cookie? Make my easy Peanut Butter Mug Cake! 

The next time you find yourself craving peanut butter cookies, whip out this single serve dessert in a matter of minutes!

Let’s discuss the basic ingredients for peanut butter cookie in a mug.

Ingredients for Peanut Butter Cookie in a Mug:

Unsalted Butter: A tablespoon of butter brings that iconic peanut butter cookie flavor to the recipe.

If you are dairy-free, you can replace it with melted coconut oil or avocado oil but note that the cookie won’t have that classic creaminess.

Creamy Peanut Butter: Use your favorite well-stirred peanut butter. I like using lightly sweetened natural peanut butter.

Other nut butters like almond butter, cashew butter, and sunflower seed butter work too as long as they are thick, sticky, and well-stirred. 

Pure Maple Syrup: Used to sweeten the cookie to perfection, we use pure maple syrup.

The cookie turns out with the perfect level of sweetness so if you prefer very sweet treats, consider adding 1 to 2 teaspoons of brown sugar or white sugar.

Egg Yolk: An egg yolk brings richness, moisture, and a little chewiness to the cookie. Unfortunately, I don’t have a good replacement for those who eat egg-free. 

Pure Vanilla Extract: A little splash of vanilla helps generate the classic flavor of traditional peanut butter cookies. If you don’t have any on hand, it’s fine to skip it.

Gluten-Free All-Purpose Flour: In order to keep the cookie gluten-free, we need a gluten-free all-purpose flour blend.

I use Bob’s Red Mill Gluten-Free 1-to-1 Baking Flour, which I find yields the best texture.

Note that if you use a different brand of GF flour, there will be variations in texture. Because gluten-free flour blends already contain leavening agents like baking powder or baking soda, there is no need to add any in.

Sea Salt: A pinch of sea salt enhances the peanut butter flavor and also the sweetness. Be sure to include it!

Chocolate Chips (Optional): Chocolate chips are entirely optional. At a minimum, I like adding some to the top of the cookie, but you can also mix some into the peanut butter cookie dough for added sweetness and fudgy texture.

I like semisweet chocolate chips but mini chocolate chips, white chocolate chips, and peanut butter chips are great options too.

If you really want to get wild, you can chip up mini peanut butter cups and stir them in. 

Now that we’ve covered the simple ingredients for a single-serve mug cookie, let’s make it!

How to Make Peanut Butter Cookie in a Mug:

Microwave the butter in a microwave-safe mug for 20 to 40 seconds, or until it has melted.

Note: I prepare the cookie dough in a small bowl or a measuring cup first and then use a rubber spatula to transfer it over to a microwave-safe mug or ramekin. You can easily just use a mug for the whole process, which requires less cleanup.

Add the peanut butter, pure maple syrup, egg yolk, and vanilla extract and mix well until everything is well-combined (wet ingredients).

Note: If your peanut butter is very cold from having been sitting in the refrigerator, microwave it along with the butter to soften it up so that it stirs easily.

Stir in the gluten-free all-purpose flour and sea salt (dry ingredients) and mix until a smooth batter forms.

The mixture will be relatively thin and will not resemble regular cookie dough – this is normal! If you’d like, sprinkle the top with chocolate chips or mix some chocolate chips into the cookie dough.

Microwave on high heat (the microwave’s default setting) for 45 to 60 seconds, or until it has set up.

I recommend starting with 45 seconds then microwaving longer only if need be. Allow the mug to cool down for a minute or two before enjoying the peanut butter cookie – initially it will be very hot!

The texture will look slightly crumbly but the cookie will melt in your mouth. Consider serving microwave peanut butter cookies with a scoop of ice cream or a glass of milk. A drizzle of chocolate sauce is never a bad idea either!

If you end up with leftovers, wrap the mug in plastic wrap or transfer the rest of the peanut butter cookie mug cake to an airtight container and refrigerate for up to 3 days. When you reheat it, add a little almond milk or butter to soften the cookie back up.

And that’s it! An easy single-serve peanut butter cookie that is ready in less than 5 minutes!

The perfect dessert for those times you’re craving something decadent but don’t want leftovers hanging around tempting you, this easy mug recipe is just picture perfect for peanut butter lovers.

Enjoy the concept of a single serve cookie? Also try my One Huge Gluten-Free Chocolate Chip Cookie. 

If you love desserts in mugs, also try out these mug recipes.

More Mug Desserts:

• Oatmeal Banana Bread Mug Cake  
• Healthy Cinnamon Roll in a Mug  
• Keto Mug Cake  
• Gluten-Free Mug Brownie  

Peanut butter cookie, ready in 5, 4, 3, 2…

Peanut Butter Cookie in a Mug

This delicious single-serve gluten-free peanut butter cookie in a mug is the perfect serving size for one or two people and takes less than 5 minutes to make!

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Prep Time: 3 minutes minutes

Cook Time: 1 minute minute

1 Cookie

Equipment

• ▢
  Microwave-Safe Mug

Ingredients

• ▢ 1 Tbsp unsalted butter*
• ▢ 3 Tbsp creamy peanut butter
• ▢ 2 Tbsp pure maple syrup
• ▢ 1 egg yolk
• ▢ ½ tsp pure vanilla extract
• ▢ 2 ½ Tbsp gluten-free all-purpose flour or regular all-purpose flour
• ▢ ⅛ tsp sea salt

Instructions

• Microwave the butter in a microwave-safe mug for 20 to 40 seconds, or until it has melted. Note: I prepare the cookie dough in a small bowl or a measuring cup first and then use a rubber spatula to transfer it over to a microwave-safe mug or ramekin. You can easily just use a mug for the whole process, which requires less cleanup.
• Add the peanut butter, pure maple syrup, egg yolk, and vanilla extract and mix well until everything is well-combined (wet ingredients). Note: If your peanut butter is very cold from having been sitting in the refrigerator, microwave it along with the butter to soften it up so that it stirs easily.
• Stir in the gluten-free all-purpose flour and sea salt (dry ingredients) and mix until a smooth batter forms. The mixture will be relatively thin and will not resemble regular cookie dough – this is normal! If you’d like, sprinkle the top with chocolate chips or mix some chocolate chips into the cookie dough.
• Microwave on high heat (the microwave’s default setting) for 45 to 60 seconds, or until it has set up. I recommend starting with 45 seconds then microwaving longer only if need be. Allow the mug to cool down for a minute or two before enjoying the peanut butter cookie – initially it will be very hot! The texture will look slightly crumbly but the cookie will melt in your mouth. Consider serving microwave peanut butter cookies with a scoop of ice cream or a glass of milk.

Notes

*Replace the butter with coconut oil, vegan butter (like Earth Balance), or avocado oil

Nutrition

Serving: 1cookie – Calories: 622kcal – Carbohydrates: 55g – Protein: 15g – Fat: 40g – Saturated Fat: 14g – Polyunsaturated Fat: 1g – Monounsaturated Fat: 5g – Cholesterol: 215mg – Sodium: 223mg – Fiber: 6g – Sugar: 31g

Course: Dessert

Cuisine: American

Keyword: desserts in mugs, gluten free dessert recipe, gluten free peanut butter cookie recipe, peanut butter cookie in a mug, peanut butter desserts, peanut butter mug cookie, single serve dessert recipe

Servings: 1 Cookie

Calories: 622kcal

Author: Julia

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