4-Ingredient Keto Peanut Butter Brownies

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Is it possible for a recipe to be too easy? Don’t let the simplicity of this one turn you off. Even though these keto brownies contain just 4 ingredients and are super-simple to make, they might just be the best ever brownies you’ve ever eaten!

These peanut butter brownies are just perfect: fudgy on the inside (if you don’t bake them too long, that is!) and crispy outside. Especially the peanut butter swirl on top: it almost has the consistency of a crunchy peanut butter cookie! And with less than 3 grams net carbs per serving, these brownies are ideal if you’re following a keto diet.

Tips for making the 4-Ingredient Keto Peanut Butter Brownies

The brownie batter is really easy to prepare: Just combine all the ingredients in a bowl, mix quickly until well combined and that’s it. Actually, it’s important NOT to overmix — always mix just until the ingredients are combined and no longer — because otherwise the brownies might turn out rubbery. I don’t know why this is, but it happens: I experienced it myself when I beat the batter for more than a minute or two.

For the sweetener, I recommend an erythritol-based brown sugar substitute such as Sukrin Gold. Sukrin Gold is my top choice for a brown sugar substitute, and that goes for these brownies, too. Regular erythritol crystals work as well, but they make the brownies slightly harder. Plus, the taste isn’t quite as “warm”.

The peanut butter swirl on top of the brownie is fully optional, but as it really adds to both the brownies’ taste and texture, I highly recommend it. Don’t worry: like the rest of this recipe, it’s super-quick and simple to make, as we’ll soon see.

Another important thing is to keep your eye on the brownies while they’re baking. Whatever you do, don’t bake them too long! You really want that fudgy interior, and that won’t happen if you overbake them. When you see the edges rising while about 3 inches (7.5 cm) of the center remain flat, that’s the correct time to remove them from the oven.

Told you these brilliant brownies were quick to make! Mix quickly, bake quickly, and you’re done.

Let’s take a look at how to make them:

Take a medium bowl. Add the ingredients; the order doesn’t matter (remember to leave some PB and Sukrin Gold aside for the swirl).

Add the peanut butter (smooth or crunchy, you choose)…

…cacao powder…

…Sukrin Gold…

…and the eggs.

Beat with an electric mixer…

…until just combined. This shouldn’t take longer than half a minute.

Transfer the batter to a greased 9×9-inch (23×23 cm) glass or ceramic baking dish. You can also use a silicone pan; then you don’t have to grease it.

Like this.

Next, take the remaining peanut butter. Place it in a small bowl and add the remaining Sukrin Gold.

Mix well. If your peanut butter is stiff, you can heat it in the microwave in 10-second spans to make it runnier and thus easier to mix and drizzle. Or, if you don’t want to use microwave, just place the PB (glass) jar into hot water and mix until runnier.

Drizzle the peanut butter and Sukrin Gold mixture on top of the brownies.

Take a spoon and create some beautiful swirls so that the peanut butter mixes with the brownie batter a bit (my swirls here could be a bit prettier, frankly!).

Bake in the preheated oven for 15-20 minutes.

Keep your eye on the brownies to avoid overbaking. This way the center will be fudgy.

Let cool until slightly warm, remove from the pan and cut into 16 pieces.

Enjoy!

My Keto Peanut Butter Brownie experiments

This recipe is another one from my long to-do list. I decided to give them a try now, since it’s finally fall; I thought they’ve be wonderfully comforting and a great way to beat the chill.

But I didn’t have a recipe for the comforting brownies I was dreaming of: all I had was—well, my dream. The brownies should definitely be slightly fudgy inside and crunchy outside, I thought. And with a peanut butter swirl on top, maybe they’d look and taste even better.

I wasn’t sure if I wanted to use pumpkin in there as well, but I realized I’d be able to make several peanut butter brownie experiments, some with pumpkin and some without. In the end, I ended up in developing both: this peanut butter brownie version without pumpkin, and another deliciously fudgy version with it. (The recipe with pumpkin is on my other, pretty freshly established blog. The one with pumpkin is also egg-free, so if you don’t tolerate eggs, you might want to try it out. (It’s also a very simple recipe: only 4 ingredients in the brownie part and 2 ingredients in the frosting! I’m enjoying some for breakfast as I write this. Yum!)

So, I had a clear idea in mind about the kind of brownies I was aiming for. For my Low Sugar, So Simple book, I had developed a fudgy brownie recipe; maybe I could use that as a starting point by adding peanut butter and removing the coconut flour?

I didn’t do too many calculations: I just wanted to start experimenting. So, for my first experiment, I took 1 cup (240 ml) peanut butter, 2/3 cup (160 ml) erythritol crystals, 1/4 cup (60 ml) cacao powder, 1 tablespoon baking powder, and 5 eggs. I beat everything together and poured the batter into a brownie pan.

After baking the brownies for 20 minutes at 350 °F (175 °C), I removed them from the oven and noticed the result was far too cake-like. Nothing fudgy there. Maybe reducing the number of eggs would yield a fudgier result? And perhaps omitting the baking powder as well?

At this point, I made my first pumpkin peanut butter brownie experiments, which turned out too fudgy and moist – almost raw! For both recipes, I needed something in between: fudgy, but not too moist and not too dry.

For my next peanut butter brownie experiment, I took 1 cup (240 ml) crunchy peanut butter, 1/2 cup = 120 ml dark cacao powder, 2/3 cup (160 ml) Sukrin Gold, and 5 eggs. Like I said, Sukrin Gold is my preferred brown sugar substitute and I thought it would be just perfect here with its warm, caramel-ish note.

I was also planning to use fewer eggs, but since the batter looked too thick after beating it for a couple of minutes, I added some more and ended up using 5 eggs. This time, I also made a peanut butter swirl on top. I had no idea if I needed more ingredients for the swirl than just PB and sweetener mixed together (perhaps an egg was necessary?), but first I tried it with just a mixture of PB and sweetener drizzled on top.

Speaking of not having a clue, I have to confess that I had no idea how to make a beautiful swirl in the brownie batter! I’d never done it before. I took a large spoon and made big, careful swirls, trying to gently mix the brownie batter with the peanut butter and sweetener mixture. To my surprise, the result was gorgeous! At least, it is to me: what do you think? (Photo below). I think it turned out even more beautiful than my later swirl experiments!

So, the resulting brownies were just perfect on top, but they were depressingly rubbery inside. What a disappointment! I was hoping for a fudgy interior, but I sank my teeth into a stiff, rubbery square. Not a nice experience!

What on earth should I change to get a properly fudgy result? Fewer eggs? More PB? More cacao powder? I decided to add more eggs just to see if the result would be fudgier. I used 1 cup (240 ml) PB, 2/3 cup (160 ml) Sukrin Gold, 1/2 cup (120 ml) dark cacao powder, and 6 eggs. Since the batter got really thick really fast when I was beating it, I decided to just mix it briefly, only until the ingredients were combined. Maybe that would help reduce the rubberiness, too? I also decided to decrease the baking time by 5 minutes.

Now the result was just perfect! I had gotten the fudgy interior I was after, plus the crisp surface. The peanut butter swirl added some crunchiness, and it also tasted heavenly! It was definitely a good idea to add it. And for this last experiment, I had increased the amount of PB in the swirl: earlier I had used only 1/4 cup (60 ml), but 1/3 cup (80 ml) worked wonderfully here.

I’m so enthusiastic about this recipe; let me know how it works for you!

Nutrition information:	Protein	Fat	Net carbs	kcal
In total:	139.2 g	200.2 g	47.1 g	2641 kcal
Per serving if 16 servings in total:	8.7 g	12.5 g	2.9 g	165 kcal

N.B. The nutritional values highly depend on brands of ingredients used. Try to choose brands that are as low in carbs as possible.

Tips for variations

You can vary the basic brownie recipe as much as you like. You can add chopped salted peanuts or dark chocolate chips to the batter, or season the batter with a dash of vanilla extract. For some reason, I prefer a hint of vanilla in my peanut butter goodies, so I often add some vanilla extract to them — especially if there is no chocolate in the recipe.

Instead of the peanut butter swirl (or even in addition to it!), you can make a simple frosting from chocolate ganache: Heat 1/2 cup (120 ml) heavy cream or coconut cream in a saucepan until piping hot. Don’t let it boil. Add 4 oz (115 g) chopped dark chocolate (cocoa content minimum 85%) and let stand 5 minutes. Mix until thick and smooth and pour evenly over the brownie before cutting it into slices. Let set in the fridge overnight. Remove from the fridge the following day and cut into pieces.

If you don’t want to make frosting, you can always drizzle melted dark chocolate on top of the brownie when it’s still warm after removing it from the oven. For ultimate indulgence (and a beautiful presentation!), you can even add sugar-free white chocolate chunks, salted crushed peanuts and/or dark chocolate chips on top before the melted chocolate sets. Dessert doesn’t get better than this!