Name: Peanut Butter Oatmeal Cookies
Prep time: 15 min
Cook time: 15 min
Total time: 30 min
Cuisine: American
Ingredients: 5 ½ cups rolled oats (gluten free); 5 large eggs; ¼ cup water; 1 tablespoon vanilla extract; 1 cup unsalted butter, softened (2 sticks); 1 ¾ cups peanut butter (crunchy or creamy); 1 ½ cups granulated sugar; 1 ½ cups light brown sugar, packed; ½ cup all-purpose flour (or GF baking flour); 1 tablespoon baking powder; 1 teaspoon salt; 12 ounce semi-sweet chocolate chips; 12 ounce M&Ms

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Why You’ll Love Peanut Butter Oatmeal Cookies Recipe

These cookies are wonderfully thick and satisfying, with a soft center and lightly golden edges. The oats add a hearty chew, while the peanut butter brings richness and depth of flavor. Chocolate chips and M&Ms make every bite extra fun and sweet, giving the cookies both a classic homemade feel and a festive touch.

This recipe is also great for feeding a crowd. With 55 servings, it is perfect when you need a large batch for gatherings or want plenty to share. You can also make them ahead, store them easily, and enjoy them throughout the week.

Ingredients

(Tip: You’ll find the full list of ingredients and measurements in the recipe card below.)

5 ½ cups rolled oats (gluten free)

5 large eggs

¼ cup water

1 tablespoon vanilla extract

1 cup unsalted butter, softened (2 sticks)

1 ¾ cups peanut butter, crunchy or creamy

1 ½ cups granulated sugar

1 ½ cups light brown sugar, packed

½ cup all-purpose flour (or GF baking flour)

1 tablespoon baking powder

1 teaspoon salt

12 ounces semi-sweet chocolate chips

12 ounces M&Ms

Directions

Preheat the oven to 350 degrees F. Line several baking sheets with parchment paper and set them aside.

In a large bowl, combine the rolled oats, eggs, water, and vanilla extract. Stir well so the oats absorb the liquid while you prepare the rest of the dough.

In the bowl of a stand mixer, beat the softened butter for about 1 minute until smooth. Add the peanut butter, granulated sugar, and brown sugar. Beat on high for 3 to 5 minutes, until the mixture looks creamy and well combined.

Scrape down the sides of the bowl with a spatula, then mix again briefly to ensure everything is evenly incorporated.

Reduce the mixer speed to low and add the flour, baking powder, and salt. Mix until combined. Gradually add the oat mixture and continue mixing until a thick dough forms.

Scrape the bowl down once more. Mix in the chocolate chips on low speed. Fold in the M&Ms by hand with a spatula, reserving a small handful for pressing onto the tops if you want the cookies to look extra colorful.

Use a large 3-tablespoon cookie scoop to portion the dough onto the prepared baking sheets, spacing the cookies about 2 inches apart.

Bake each batch for 15 to 17 minutes, until the edges are lightly golden and the centers still look slightly underbaked. Let the cookies cool on the baking sheets for 5 minutes before transferring them to a wire rack to cool completely.

Servings and timing

This recipe makes about 55 cookies and takes around 30 minutes from start to finish, depending on how many batches you bake at once.

Prep time: about 10 to 15 minutes

Bake time: 15 to 17 minutes per batch

Total time: about 30 minutes

Servings: 55 cookies

Variations

For a nuttier texture, use crunchy peanut butter instead of creamy. If you prefer a more classic cookie appearance, skip the M&Ms and use extra chocolate chips instead.

To make the cookies feel more festive, swap the M&Ms for seasonal colors depending on the holiday or occasion. You can also add chopped peanuts for extra crunch, or use gluten-free baking flour and certified gluten-free oats to make the recipe more suitable for gluten-free needs.

For a slightly different flavor twist, try mixing in butterscotch chips, peanut butter chips, or dark chocolate chips in place of some of the semi-sweet chocolate chips.

Storage/Reheating

Store the cooled cookies in an airtight container at room temperature for up to 5 days. To keep them soft, you can place a small piece of bread in the container with the cookies.

For longer storage, freeze the cookies in a freezer-safe container or bag for up to 3 months. Place parchment paper between layers if needed to prevent sticking. Thaw at room temperature before serving.

To reheat, warm a cookie in the microwave for about 8 to 10 seconds to bring back that fresh-baked softness and make the chocolate slightly melty again.

FAQs

Can I use quick oats instead of rolled oats?

Yes, but the texture will be a little softer and less chewy. Rolled oats give these cookies more structure and heartiness.

Can I use creamy peanut butter?

Yes, creamy peanut butter works very well in this recipe and creates a smoother texture. Crunchy peanut butter adds extra bits of peanut flavor and crunch.

Do I need a stand mixer?

No, but it does make the process easier. A hand mixer can also work, especially if you have a large mixing bowl.

Why do the centers look slightly underbaked?

That is exactly what you want. The cookies continue to set as they cool, which helps keep them soft and chewy instead of dry.

Can I make these cookies gluten-free?

Yes, use certified gluten-free oats and a gluten-free baking flour substitute to make them gluten-free.

Can I freeze the cookie dough?

Yes, you can scoop the dough onto a tray and freeze the portions until firm. Then transfer them to a freezer bag and bake later, adding a minute or two to the baking time if needed.

How do I keep the cookies soft?

Do not overbake them, and store them in an airtight container once fully cooled. A short microwave warm-up also helps restore softness.

Can I leave out the M&Ms?

Yes, the cookies will still be delicious without them. You can replace them with more chocolate chips or another mix-in of your choice.

What is the best way to portion the dough?

A large 3-tablespoon cookie scoop is ideal for evenly sized cookies that bake consistently.

Can I make smaller cookies?

Yes, you can make smaller cookies if you prefer. Just reduce the baking time slightly and watch for lightly golden edges.

Conclusion

Peanut butter oatmeal cookies are the perfect combination of chewy, soft, sweet, and satisfying. With rich peanut butter flavor, hearty oats, and plenty of chocolate in every bite, this recipe is a dependable favorite for both everyday baking and special occasions. Whether you keep them classic or try one of the variations, these cookies are sure to disappear fast.