Buttermilk Brownies with Peanut Butter Frosting

These classic Buttermilk Brownies are rich and fudgy and topped with a creamy peanut butter frosting (my favorite combination!). This recipe is perfect for a party because it makes an entire sheet pan of brownies.

Our grandma made the best buttermilk brownies (also known as Texas Sheet Cake) – her recipe is a timeless classic that has been a family favorite for generations!

I decided to make a pan of her brownies but instead of topping it with her usual chocolate frosting, I added my favorite thing to compliment the brownies: peanut butter!

This creamy peanut butter frosting is lick-the-spoon good. I drizzled some melted chocolate on top and sprinkled Reese’s Peanut Butter Pieces all over . . . this is pretty much all my chocolate peanut butter dreams coming true!

Why is it called Texas Sheet Cake?

I have always wondered why they call it Texas Sheet Cake – I’ve heard that the recipe originated in Texas in the 1950’s and I have also heard that it’s called that because the cake is so huge and perfect for feeding a crowd the size of Texas.

Regardless of the name, it’s delicious!


How to make your own buttermilk

Buttermilk is not usually an ingredient that purchase and if you don’t have any on hand, don’t worry!! There is an easy way to make your own at home.

To make your own buttermilk, simply mix together 1/2 cup milk with 2 teaspoons white vinegar or lemon juice (either one will work). Let the milk sit for at least 5 minutes before adding it into the mixture. That’s it!

How to make Buttermilk Brownies

Buttermilk brownies are made a little differently than regular brownies . . . you start on the stove top!

  • Bring butter, shortening, water, and cocoa to a boil
  • Remove from heat and mix in flour and sugar
  • Add in buttermilk, eggs, baking soda, and vanilla – mix it all together
  • Pour into a large sheet pan
  • Bake at 400 degrees for 15-18 minutes
  • Spread with peanut butter frosting and top with candies (if desired)


Items needed for making this recipe:

  • Baking Sheet: This is my go-to sheet for any sheet pan recipes or cookies. I love this brand and use these all the time!
  • Large Wooden Mixing Spoon: I love this brownie recipe because you don’t need a mixer – you can just mix it by hand with a wooden spoon. I love how large this one is – it gets the job done!
  • Mixing Bowls: Everyone needs some good mixing bowls and these are the same ones that I have had since I got married 15 years ago. They last forever!

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We are so excited to share these recipes with you. Order your copy today!

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Looking for more sheet pan recipes to feed a crowd? Try these:

Serves: 24

Buttermilk Brownies with Peanut Butter Frosting

15 minPrep Time

18 minCook Time

33 minTotal Time

Save RecipeSave Recipe


  • 2 cups flour
  • 2 cups sugar
  • 1/2 cup butter
  • 1/2 cup shortening
  • 1 cup water
  • 1/4 cup cocoa
  • 1/2 cup buttermilk
  • 2 eggs
  • 1 teaspoon baking soda
  • 1 teaspoon vanilla
  • Frosting:
  • 1 (8 ounce) package cream cheese (softened)
  • 1/2 cup unsalted butter (softened)
  • 4 cups powdered sugar
  • 2/3 cup creamy peanut butter
  • Topping (optional):
  • 1 cup chocolate chips (melted)
  • 1/2 cup Reese's Pieces candy


  1. In a large mixing bowl, combine the flour and the sugar. Set aside.
  2. In a medium saucepan, combine butter, shortening, water, and cocoa. Stir and heat to boiling.
  3. Pour boiling mixture over the flour and sugar in the bowl.
  4. Add the buttermilk, eggs, baking soda, and vanilla to the mixing bowl. Mix well using a wooden spoon or high speed on an electric mixer.
  5. Pour into a well-greased baking sheet (17.5" x 11") pan.
  6. Bake at 400 degrees for 15-18 minutes or until brownies test done in center.
  7. To make the frosting, mix cream cheese and butter together with a mixer until completely incorporated. Add in powdered sugar and peanut butter and mix well. If it's too thick, thin it out with a little bit of milk. If it's too thin, add some more powdered sugar.
  8. Spread frosting on cooled brownies.
  9. If desired, drizzle melted chocolate chips over frosting and sprinkle Reese's pieces candies on top.



8592 cal


403 g


1240 g


102 g
Click Here For Full Nutrition, Exchanges, and My Plate Info

Frosting recipe from Center Cut Cook

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Comment on this Recipe

2 Responses to “Buttermilk Brownies with Peanut Butter Frosting”

    • The recipe already calls for 1/2 cup butter. We have only made this as directed on the recipe. If you have used Kerry Gold Butter in place of shortening in other recipes and had success, I'm sure it would work with these brownies too. We have not used Kerry Gold before.

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