Easy Peanut Butter Cake
Published Mar 14, 2022•Updated Mar 29, 2023
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Easy Peanut Butter Cake is a tender, moist cake loaded with peanut butter flavor. There’s no softened butter and no mixer needed, so you can make this 8×8 cake in no time at all.
Snacking cakes are the name of the game for busy home cooks who love a quick baking project (*raising my hand*). This is a cake that requires minimal effort to mix up after school or pop in the oven while eating dinner. When it comes to snacking cakes, these chocolate and vanilla versions have long been regulars around here, but today a peanut butter version joins the team!
So What, Exactly, Is a Snacking Cake?
Snacking cakes are the simplest of cakes that are baked in an 8-inch square or round cake pan. They are mixed up in a bowl or two, don’t require a mixer, use pantry staples, and need little more than a dusting of powdered sugar to finish (though frosting is always welcome). These cakes aren’t overly sweet, making them perfect to have with a mug of coffee or tea, as an afternoon pick-me-up, or as an easy dessert.
I created my first snacking cake recipe back in 2013 (it’s been updated since) and rarely make any other type of cake (unless I have a craving for this peanut butter cookie cake!). This category of baking has really had a moment, and Yossy Arefi even published an entire cookbook on the subject. It’s a great cookbook too!
How to Make Peanut Butter Cake
- Preheat your oven to 350°F / 177°C.
- Get an 8×8 pan ready (parchment paper and nonstick cooking spray will make the cake a breeze to remove from the pan).
- Heat butter, water, and peanut butter together until simmering.
- Whisk together dry ingredients (flour, sugar, and baking soda).
- Combine warm ingredients and dry ingredients. Set aside.
- Whisk together egg, sour cream, and vanilla.
- Combine everything in one bowl.
- Bake until just set, 20 to 24 minutes.
I discovered this method for making peanut butter cake via the Pioneer Woman’s Peanut Butter Sheet Cake. And while my version is quite different from hers in all other respects (measurements, steps to combine ingredients, and size of the cake), I am convinced that this method of melting the butter and peanut butter together first is the secret to a moist peanut butter cake that is also very easy to mix.
I can’t wait for you to try this cake! If you do, share over on Instagram and tag me @inquiringchef. I love seeing what you make!
More 8×8 Snacking Cakes
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Easy Peanut Butter Cake
- Mixing Bowls
- 8×8 baking pan
- 1 stick (8 Tablespoons) Unsalted Butter
- 1/2 cup Water
- 1/2 cup Creamy Peanut Butter
- 1 cup All-Purpose Flour
- 1 cup Sugar
- 1 teaspoon Baking Soda
- 1 large Egg
- 1/4 cup Sour Cream (sub plain or Greek yogurt)
- 1/2 teaspoon Pure Vanilla Extract
- Powdered Sugar, for dusting
- Preheat oven to 350°F / 177°C.
- Grease an 8×8 cake pan and line it with parchment paper.
- In a small saucepan over medium-high heat (or in the microwave), heat butter, water, and peanut butter, stirring continuously, until butter is melted and the mixture is simmering.
- In a mixing bowl, whisk together flour, sugar, and baking soda.
- Pour boiling liquids over flour mixture and stir until evenly combined. Set aside and allow it to cool slightly.
- In a small mixing bowl, beat egg. Add sour cream and vanilla and whisk well.
- Add egg mixture to peanut butter batter and stir just until combined. Pour into cake pan.
- Bake until cake is set in the middle and a tester inserted comes out clean, 22 to 24 minutes.
- Let cake cool completely before removing from pan.
- Dust with powdered sugar just before serving.
Nutrition information is automatically calculated, so should only be used as an approximation.