
These confetti squares flew off the plate at our potluck dinner - gone faster than anything else on the sweet table! There's something magic about mixing butterscotch, peanut butter and those tiny rainbow marshmallows that hits the spot for everybody from little kids to grown-ups.
My next-door neighbor's kid was jumping up and down with joy when she tried one, and my hubby (who swears he doesn't like desserts) snuck three while I was busy in the other room!
What You'll Need
- Butterscotch chips: They're the backbone of the flavor. Don't swap them for white chocolate - it won't turn out right!
- Peanut butter: Creamy gives you that velvety feel, but chunky adds some nice texture if that's what you like.
- Butter: The salt in salted butter cuts through the sweetness. If you've only got unsalted, toss in a tiny bit of salt.
- Vanilla extract: A small splash brings everything together without standing out too much.
- Mini marshmallows: The rainbow ones truly make these "confetti" squares. Surprisingly, the fruity flavors work really well with the butterscotch.

How I Make Them
Melt It RightI grab a thick-bottomed pot and keep the heat low while melting the butterscotch chips, peanut butter and butter together. Don't rush this part - high heat can make your butterscotch clump up or turn bitter.
Marshmallow TrickYou need to let the mixture cool a bit before dumping in the marshmallows. Too hot and they'll dissolve completely, too cold and you can't mix properly. I just touch it with my finger - when it feels warm but doesn't burn, that's the sweet spot.
Smart SettingI put parchment paper in my pan with extra hanging over the sides. This way I can lift everything out easily when it's time to cut. A quick spray of cooking oil on the paper means nothing will stick.
Smooth SlicingFor really pretty squares, I make sure they're totally chilled, then use a big knife dipped in hot water (and dried off) between cuts. You'll get those Instagram-worthy clean edges.
I first had these at my friend's house from Canada - they're apparently a big thing there where folks call them "marshmallow squares" or "peanut butter marshmallow squares." Now I bring them to every get-together when I need something fast that looks like I tried harder than I did!
Serving Ideas
They're fantastic by themselves, but sometimes I pair them with a scoop of vanilla ice cream for a fancy dessert. They work great at bake sales, for classroom snacks, or on holiday cookie trays. I've even broken them up as an ice cream topping - it's so good!
Make It Your Own
Try mixing in a spoonful of Nutella before it hardens for a chocolate twist. Throw in some Rice Krispies if you want more crunch. For a boozy version, add a few spoonfuls of bourbon with the vanilla. During holidays, grab season-colored marshmallows (red/green at Christmas, orange/black at Halloween) to match the occasion.
Storage Smarts
They stay fresh in a sealed container at room temp for many days, though they rarely hang around that long! If you want to save them longer, freezing works great - just put paper between layers so they don't stick. I often make twice as much and freeze half for when surprise guests drop by.

Insider Tricks
- For extra pizzazz, save some colorful marshmallows to scatter on top before it sets
- A light sprinkle of fancy sea salt creates an amazing flavor contrast
- Can't find colored marshmallows? White ones work too - just add food coloring to your butterscotch mix for that confetti look
These confetti squares give you way more bang for your buck than you'd expect. There's something about butterscotch and peanut butter together that creates this can't-stop-eating flavor that feels cozy yet special. And they're almost impossible to mess up - perfect when you need a guaranteed hit without any kitchen stress!
Recipe FAQs
- → Is it okay to swap marshmallows?
- Sure! Use regular white minis or chop up full-sized ones if needed.
- → Why did my marshmallows disappear?
- Your butterscotch mix might've been too hot. Cool it slightly first, but not too long.
- → Can other nut butters work here?
- Absolutely! Almond butter or any nut butter will do just fine.
- → Should I keep these in the fridge?
- Yep! Pop them in an airtight container in the fridge for up to a week.
- → Can I freeze them for later?
- You bet! They'll keep in the freezer for three months. Just thaw first.