Toasted Fluffernutter Sheet Cake

Toasted Fluffernutter Sheet Cake
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Yes, this is a Toasted Fluffernutter Sheet Cake. Yes, like the official sandwich of Massachusetts. And yes, the fluffernutter is the official sandwich of Massachusetts. I looked it up. The fluffernutter sandwich gets a lot of flack due to its use of bottled marshmallow cream and utter lack of nutrition. And yeah, okay I can see where people are coming from. Marshmallow cream is generally not part of a high-brow balanced breakfast. But what if you swapped the processed cream for the more respectable Italian Meringue and moved the peanut/marshmallow pairing to a more suitable time of the day, i.e. dessert? Not so trashy afterall.

Ingredients for the peanut butter sheet cake

Now, for those of you who grew up with Fluff in your cupboards, I’m sure you require no explanation for this sheet cake’s name. I did not grow up with Fluff, so I didn’t know what a fluffernutter was until I was 17. My friend Chelsea offered one to me and I was perplexed at the prospect. And then, a little ashamed I liked the sandwich so much. It’s definitely not “sophisticated” – I don’t think it’s even technically lunch. So if you don’t know about the fluffernutter sandwich, don’t feel bad. I didn’t know what the heck it was either.

Pour the sheet cake batter into a prepared pan.

The fluffernutter sandwich hit the scene during World War I but didn’t get its name until 1960. It was coined by the advertising firm Durkee-Mower, which sounds about right to me. Fluffernutter is a painfully cutesy name for a lunch item that almost promises diabetes. But that’s a matter for a different day.

Spreading the batter into an even layer.

This weekend is Father’s Day. And while I am nowhere near my father physically this year, I thought I’d make him a cake. I know it may seem cruel to serve a person a cake digitally but I promise I do this with only the best intentions. I decided on this Toasted Fluffernutter Sheet Cake for my dad because he taught me how to build a bonfire and he is a devoted fan of peanut butter – possibly peanut butter’s biggest.

Swirling the peanut butter into the cake batter

If my dad taught me one thing, it was to love peanut butter. Well, my dad taught me lots of things, but the peanut butter thing really stuck. I may never love the stuff quite as much as he does – he regards it as its own food group – but I’ve got to be getting close. I eat it every morning without fail, sometimes on toast and sometimes smeared on a banana or apple slices – don’t knock it till you’ve tried. And there have been times, in my post-run hunger haze, when I’ve eaten peanut butter by the spoonful. It’s made it into a number of my recipes and any ice cream with a peanut butter swirl is automatically my favorite. But even with all these daily devotions, I am not remotely peanut butter’s biggest fan. That is and always will be my father.

Italian Meringue

When I was young, my father went into work extremely early. He did this so he could be home for dinner almost every night. Us kids, would almost always sleep through his departure. But I do have a handful of memories of waking up in the dark and early hours to find my father eating breakfast at the kitchen table. It was always the same breakfast – a slab of my mom’s bread slathered with peanut butter and honey. The bread was always folded over on itself – like a lazy sandwich.

Spreading the Italian Meringue on the peanut butter sheet cake
Toasting the Meringue with a kitchen torch

When I was lucky enough to catch him in the morning, he’d make me my own folded-over-sandwich and we’d chat at the kitchen table, while my mom and siblings slept. These always felt like unicorn moments. They almost never happened and when they did they felt unique and exclusive. Maybe that’s why I gravitate to peanut butter – they remind me of those dark, quiet mornings with my dad. 

So now that you understand my relationship with peanut butter and my dad’s deep love for the stuff – I’m sure this Toasted Fluffernutter Sheet Cake is starting to make a whole lot of sense. What better way to celebrate my dad than with a peanut-heavy sheet cake topped with a layer of toasted Italian Meringue. And to really make it his, I added a sprinkle of sea salt to the cake as a final flourish. I do realize he’s probably less than pleased he has to enjoy this cake virtually. But alas, this is COVID’s world and we’re just living in it. I dearly wish I could serve him the corner piece in the flesh.

So, that’s everything you need to know about this Toasted Fluffernutter Sheet Cake. This dessert is nostalgic, salty/sweet heaven. And what’s more, it surprisingly easy to pull off. It doesn’t get better than this.

Happy Father’s Day! Enjoy!

Toasted Fluffernutter Sheet Cake

This Toasted Fluffernutter Sheet Cake features a fluffy peanut butter cake covered with a blanket of toasted meringue topped with a smattering of peanuts and a sprinkle of finishing salt.
Prep Time 30 minutes
Cook Time 50 minutes
Course Dessert
Cuisine American
Servings 12


  • Kitchen Torch
  • 9×13 baking pan


Peanut Butter Sheet Cake

  • 1 cup unsalted butter softened
  • ¾ cup brown sugar
  • ½ cup granulated sugar
  • 3 eggs room temperature
  • 1 ½ cups smooth peanut butter divided
  • 1 tsp vanilla extract
  • 2 ¼ cups all purpose flour
  • 2 tsp baking powder
  • ½ tsp salt
  • 1 cup whole milk

Italian Meringue

  • ¾ cup granulated sugar
  • ½ cup water
  • 3 egg whites room temperature
  • ½ tsp cream of tartar


  • whole peanuts for sprinkling
  • chopped peanuts for sprinkling
  • finishing salt for sprinkling


For the Sheet Cake

  • Preheat the oven to 350°F. Grease a 9×13" baking pan and line with parchment paper. Set aside.
  • Place the butter, brown sugar and sugar in the bowl of a stand mixer fitted with a paddle attachment. Cream the sugar into the butter until light and fluffy. Beat the eggs into the butter mixture one at a time. Wait for each egg to be fully integrated before adding the next one.
  • Once the eggs at integrated, add 1 cup of the peanut butter and the vanilla extract. Beat until well mixed.
  • In a large bowl, whisk to combine the flour, baking powder, and salt. Add ½ of the flour mixture to the mixer and beat until combined. Add half of the milk and beat once more until combined. Repeat with the remaining flour mixture and milk until both are well-integrated.
  • Pour the batter into the prepared pan and smooth the surface with an offset spatula. Dot the surface with ½ teaspoon dollops of the remaining peanut butter and swirl it into the batter using a butter knife. Transfer the cake to the oven and bake for 35-40 minutes or until golden and set in the middle.
  • Let the cake cool for 10 minutes in the pan before inverting it onto a cooling wrack. Peel the parchment off of the cake and discard it. Let the cake cool completely.

For the Meringue

  • Once the cake has cooled, make the meringue. Place the sugar and water in a saucepan and place over high heat. Heat the mixture until it registered 240°F on a candy thermometer.
  • While the sugar/water mixture is heating up, place the egg whites in the bowl of a stand mixer fitted with a whisk attachment. Add the cream of tartar and whip on high until soft peaks form.
  • Once the peaks have formed and the sugar water has reached the proper temperature, whisk the egg whites on high while carefully pouring the sugar water into the mixing bowl in a steady, thin stream. Whisk until stiff peaks form.

To Assemble

  • Spoon the meringue onto the surface of the cake. Using an offset spatula, spread the meringue to form a relatively even layer with pleasing swoops and swirls.
  • Using a kitchen torch, toast the meringue until golden. Top with whole and crushed peanuts and finish with a sprinkling of salt. Slice and serve immediately.
Keyword fluffernutter, meringue, peanut butter, sheet cake

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