Peanut Butter Fudge Cake

Oh, peanut butter and chocolate, how I love you. Seriously, I never seem to get tired of that classic combination. I’ve used that famous duo in cookies, cheesecake, cake, brownies, pie, and more. And, I don’t plan on stopping any time soon.

If you follow my baking adventures, you know that I’m not much on pretty, elaborate desserts. I may make something like that occasionally, but my practical side says that simple is the way to go more often than not. I’m betting most of you are with me on that, too.

This cake is one of those lovely one-layer kind. It’s made very much like a Texas Sheet Cake, with some cooking on the stovetop for both the cake and the icing. The chocolate cake is moist and dense and just lovely. It has a nice, delicate chocolate flavor. That’s a good thing, because the icing is not even remotely subtle in the chocolate department.

The peanut butter filling couldn’t be simpler. It’s peanut butter. Seriously. Spread it on the cake while it’s still warm, and the peanut butter will make a lovely, tasty layer between the cake and the icing.

Peanut Butter Fudge Cake is a must for fans of chocolate and peanut butter. Such a crowd-pleaser!

I love this kind of icing. It’s simple to make, so that’s always a plus. And, it’s so soft and gooey. It goes on the cake while it’s warm, and then it hardens and sets as it cools. It forms some kind of serious shield over the cake. Don’t be alarmed if the icing cracks and crinkles when you cut into it. That’s just the nature of this kind of icing. If it bothers you, that’s why some very smart person invented garnishes. Maybe some chopped peanut butter cups?

This cake is what’s known as a crowd-pleaser. First of all, it makes enough for a crowd. Secondly, it’s chocolate and peanut butter, so what’s not to like?

As is always the case when chocolate is the center of attention, be sure to use a good quality cocoa powder for the best results. I used one of my favorites, Scharffen Berger unsweetened natural cocoa powder.

I made this cake to help out my blogging friend Erin of The Spiffy Cookie. She is finishing up her dissertation and asked for a little help from some fellow food bloggers.

Click here for the recipe.

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  1. Kayle (The Cooking Actress) September 12, 2013 Reply

    yessssssssssssssssssss-so happy you posted this on Spiffy Cookie! LOOVE

  2. becca @ Crumbs September 12, 2013 Reply

    my oh my these look good! peanut butter and chocolate is a favourite combination of mine too!

  3. Amanda @ Once Upon a Recipe September 12, 2013 Reply

    Ermagerd. This cake! I’d just love to sink my teeth into a big fat slice. How decadent!

  4. JEP September 12, 2013 Reply

    This cake will be perfect in every way. I cannot imagine a better tasting cake than this one:)

  5. marcie @ Flavor the Moments September 12, 2013 Reply

    This looks like the perfect cake creation, because I love peanut butter and chocolate!

  6. Tracy {pale yellow} September 12, 2013 Reply

    Oh my! This looks fantastic, I can’t wait to make one for myself!

  7. Joanne September 12, 2013 Reply

    Peanut butter and chocolate always always always sounds good to me! Love that layer of icing!

  8. Kathy September 12, 2013 Reply

    I will never get tired of peanut butter and chocolate either! So good. This cake looks incredible. Love the layered frostings!

  9. Catherine September 14, 2013 Reply

    Wow – this looks incredible! I can eat a whole tub of peanut butter by itself but added to chocolate cake, I die! This discovery is not going to do my waistline any favours! x

  10. Peanut butter + chocolate = heaven! Looks so good :)

  11. Shelly (Cookies and Cups) September 15, 2013 Reply

    This looks so good! Peanut butter and fudge go along so well =)

  12. Christina R September 19, 2013 Reply

    I made this cake last night, and I have to say, it’s the BEST fudge cake in the world! So decadent and rich, you only an eat a small square at a time. Tastes like a layer of homemade fudge on top of rich chocolate cake…I actually swirled the top icing a bit, and as it set it actually did look like a huge block of homemade fudge…so much so that when my husband cut into it he said,”oh, there’s cake underneath!”

  13. Stephanie @ PlainChicken September 25, 2013 Reply

    I am making this next week. I LOVE peanut butter and chocolate. This looks like heaven!

  14. My 2 favorite flavor combinations! sounds yummy!

  15. stacie sperlazza January 15, 2014 Reply

    I like it

  16. stacie sperlazza January 15, 2014 Reply

    I like it it looks good

  17. Adrian Bates January 17, 2014 Reply

    I made this cake about 20 years ago.

  18. Adrian Bates January 17, 2014 Reply

    I made 2 versions of this cake

  19. David January 19, 2014 Reply

    When making the cake, it seemed that the egg started to cook when you added it to the butter, coca, buttermilk and water and then brought that to a boil. Is this the way it should be or am I doing something wrong? When I pulled the cake out of the oven, it looks normal, but there were definitely small pieces of cooked egg in the batter. Thanks for any help you can give.

    • Lisa February 23, 2014 Reply

      We were wondering the same thing! Weird.

      • Author
        Jennifer McHenry February 23, 2014 Reply

        Hi, David and Lisa! I didn’t have that problem, but I think the key is the constant stirring.

  20. Lorraine January 19, 2014 Reply

    Made this tonight and it turned out delicious. Will definitely make this again…over and over :)

  21. Jana Frei February 26, 2014 Reply

    The recipe did not say how much baking soda to add to the flour and sugar mixture. How much?

  22. Kristin felts March 6, 2014 Reply

    I had the problem with the egg cooking as well, and I was constantly stirring it. I think maybe it heated too quickly. Despite the chewy but here and there the cake was delicious. I think I will cut the peanut butter in half next time. It was a bit much.

    • Sarah January 23, 2015 Reply

      Hey Kristin, a trick in baking that I have learned is break the eggs in a separate bowl and add a little of the hot mixture to the eggs while stirring constantly. This helps bring the eggs to the same temp as the hot mixture without cooking the eggs. Makes it easier to mix the eggs into the hot mixture.

  23. Sandy B November 3, 2014 Reply

    So glad I found your site. I love baking……just retired from work & so excited to start baking for my family & friends.

    • Author
      Jennifer McHenry November 4, 2014 Reply

      Welcome, Sandy! I hope you find plenty of new favorite recipes!

  24. Rachel March 5, 2015 Reply

    Oh, how I love this combination, peanut butter and chocolate.

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