Keto Halloween Peanut Butter Cup Cookies
Published October 11, 2020 • Updated February 27, 2026
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I press sugar-free peanut butter cups right into flourless cookie dough, then decorate them as creepy spiders and zombies for a fun keto Halloween treat.
Every October, I look for keto treats that are actually fun to make and not just “healthy versions” of the real thing. These Halloween peanut butter cup cookies are the ones I keep coming back to. They take about 20 minutes of actual work, and my kids get to do the decorating part, which is the whole point.
The cookie base is flourless. Just peanut butter, sweetener, an egg, and vanilla. If you’ve made my chewy keto cookies, you already know this dough. It holds together without any almond flour or coconut flour, and the texture stays soft in the center with slightly crisp edges. If your kitchen runs warm, the dough gets sticky fast. I pop the bowl in the fridge for 10 minutes and it firms right up. Roll each ball to about 1 inch, then press a sugar-free cup right into the top before baking.
Here’s what I learned after making these three Halloweens in a row: 7 minutes at 350 degrees is the sweet spot. I know that sounds short. Most similar recipes say 8-10 minutes, but that over-bakes the edges and makes the cup center too melty. Pull them at 7 and get them into the fridge for 15 minutes. That cooling step firms everything up so the candy stays intact when you start decorating.
The decorating is where it gets fun. I melt sugar-free chocolate chips and load them into a piping bag (or a zip-lock with the corner snipped, which I actually prefer for more control). For spiders, I pipe eight legs radiating from the center and stick on candy eyes while the chocolate is still tacky. For zombies, I tint melted white chocolate with green food coloring and pipe messy hair and a jagged mouth. The trick is piping while the chocolate is still slightly warm, or the legs won’t stick to the cookie surface. My kids fight over who gets to place the candy eyes.
I use two sweeteners in the dough: monk fruit blend for bulk and golden monk fruit for a deeper, almost caramel-like sweetness. Single-sweetener versions taste flat to me. If you don’t have golden monk fruit, my keto chocolate chip cookies use the same dual-sweetener approach and I explain the difference there.
These work great alongside other low carb Halloween treats. I usually make a whole spread: these spider cookies, my Halloween rice krispie treats, sugar-free candy corn, and sometimes the chocolate graveyard cake. The cookies store well in an airtight container at room temperature for about a week. For longer storage, I freeze them without the chocolate decorations for up to 3 months, then thaw at room temp and decorate fresh. I’ve been making these for at least five Halloweens now, and they’re the one seasonal recipe I never skip.
Three Ways to Decorate These Halloween Cookies
I’ve made these three different ways. The classic spider (eight chocolate legs + candy eyes) is the easiest and works for all ages. The zombie (green-tinted white chocolate hair and mouth) takes a steadier hand but looks amazing. And my favorite shortcut for little kids: simple circle faces with two dots for eyes and a zigzag mouth piped in dark chocolate. Kids under 6 can handle those on their own. I keep all three designs in rotation depending on who’s helping me in the kitchen. For more Halloween baking, my Jack O’Lantern cookies use a different dough base and the ghost meringue cookies are a fun change of texture.
Ingredients
1 cup of creamy peanut butter -
1/4 cup monk fruit blend sweetener
-
2 tablespoons golden monk fruit
-
1/4 teaspoon salt
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1 teaspoon vanilla
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1 egg
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15 sugar-free peanut butter cups
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1/3 cup sugar-free chocolate chips, melted
Step by Step Instructions
Step by Step Instructions
Pinch & roll dough
Pinch off some cookie dough and roll it into a 1-inch ball. Place on a parchment-lined baking tray.
Make dough balls
Press sugar-free peanut butter cup into each dough ball. Repeat with remaining dough.
Bake it
Bake at 350 degrees for 7 minutes. Remove from oven and cool in the refrigerator for 15 minutes.
Piping bag time
Add melted sugar-free chocolate chips to a piping bag. Pipe spider legs and top with candy eyes.
Nutrition disclaimer
The nutrition information provided is an estimate and is for informational purposes only. I am a Doctor of Pharmacy (Pharm.D.); however, this content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always consult your physician or other qualified health provider before making any lifestyle changes or beginning a new nutrition program.
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Get My Macros + Recipes →Frequently Asked Questions
Can I freeze these cookies?
I freeze these all the time. My approach is to freeze them before decorating, because the chocolate spider legs and zombie faces can crack during thawing. I lay the plain baked cookies in a single layer on a sheet pan, freeze for an hour, then transfer to a zip-lock bag. They keep for up to 3 months. When I'm ready to serve, I thaw at room temp for about 20 minutes and decorate fresh.
How long do these stay fresh at room temperature?
I've kept them on the counter in an airtight container for a full week with no issues. The flourless dough actually stays softer longer than flour-based cookies in my experience. After about day 5, the edges lose some of their crispness, but the center stays chewy. If you decorated them with chocolate, the decorations hold up fine at room temp.
What sweetener can I use instead of golden monk fruit?
I use golden monk fruit for that deeper, almost caramel-like sweetness it adds. If you can't find it, I'd sub in brown Swerve or golden allulose. Regular monk fruit works but the cookies taste a little one-note to me. The golden variety adds a warmth that reminds me of brown sugar cookies from before I went keto.
Why are my cookies crumbling apart?
I've had this happen when the dough is too dry, usually from measuring the sweetener too generously. If your dough feels sandy and won't hold together when you squeeze it, try adding a tablespoon more of the nut butter. I've also found that letting the dough rest for 5 minutes after mixing gives the egg time to bind everything. Make sure you're rolling gently, not pressing too hard.
Can I make these without eggs?
I've tested a flax egg version (1 tablespoon ground flax + 3 tablespoons water, rested for 5 minutes) and it works. The cookies are slightly more fragile and don't spread as much, so I press them a bit flatter before baking. The taste is the same. I wouldn't skip the egg replacement entirely though, because the dough won't hold the cup in place without some kind of binder.
What's the best way to pipe the spider legs?
I snip a tiny corner off a zip-lock bag (smaller than you think, about 1/8 inch). The chocolate needs to be warm but not hot. If it's too hot, the lines pool and spread. If it's too cool, they crack and won't flow. I microwave in 15-second bursts and stir between each one. For the legs, I pull outward from the center in one smooth motion and do all 8 on one cookie before moving to the next so the chocolate stays workable.
How do I keep the candy cups from melting during baking?
This is why I only bake for 7 minutes. Most recipes suggest 8-10, and every time I've gone past 7 at 350 degrees, the cups start to soften and lose their shape. The 15-minute fridge rest right after baking is non-negotiable for me. It re-firms everything. I also press the cups in after rolling the dough balls (not before), so they sit on top rather than getting buried in warm dough.
What other Halloween treats go with these?
I make a full spread every October. The Jack O'Lantern cookies on my site use almond flour for a crunchier base, and my ghost meringues are almost zero carb. I've also done the rice krispie treat version for years. The spider and zombie cookies from this recipe are always the first to disappear though, so I double the batch.
These Halloween peanut butter cup cookies have to be the cutest Halloween cookie I’ve made. My kids flipped for these when I first made them and they demanded that we make them together ASAP! Luckily, this cookie recipe is very easy to make so it’s an easy one to get your kids involved with. Plus it only takes about 30 minutes to make.
These keto cookies are for my peanut butter and chocolate fans. The cookie base is a peanut butter cookie that surrounds a creamy, sugar-free peanut butter cup.
Decorate these as spiders or zombies. Both are fun options that everyone will enjoy – especially if you are serving them at a Halloween party!
ChocZero has three different varieties of low carb peanut butter cups – dark chocolate, milk chocolate and white chocolate. For this recipe, I used all three flavors. I used the sugar-free dark and milk chocolate peanut butter cups to make the spider cookies. I used the white chocolate peanut butter cups to make the zombie cookies.
Pressing the peanut butter cups into the dough hit me with a memory I wasn't ready for. Reese's were my whole Halloween as a kid (I used to save the wrappers because I wasn't done with them), and I genuinely thought that was behind me on keto. That first bite on a Tuesday in February hit exactly right.
Saving the wrappers because you weren't done with them. That part got me. A random Tuesday in February is somehow the right time for something you thought was off the table for good.
Made keto peanut butter cookies a bunch of times and they always came out dry and crumbly, so I wasn't expecting much. Pressing the sugar-free peanut butter cup into the center makes it actually feel like a treat though. Still not sold on the monk fruit aftertaste but this is the one I'll keep making.
The monk fruit aftertaste is real. Try golden allulose instead, same ratio, way cleaner finish.