My sister brought these over for a spring gathering and we devoured them. Just 4 ingredients. Make mini foil wrapped squares and stack them up so nobody knows the sweet surprise inside until they open

These slow cooker 4-ingredient foil wrapped grasshopper brownies are the kind of dessert my sisters and I pass around at spring gatherings and potlucks. They’re rich, minty, and chocolatey, but the real fun is in the little foil-wrapped squares—no one knows what’s inside until they peel one open. Everything bakes together right in the slow cooker, so you can set it and forget it while you get the house ready or wrangle kids. With just a boxed brownie mix, a simple minty filling, and a drizzle of chocolate syrup at the end, this is a cozy, low-stress treat that feels a little bit special and a lot like home.

Serve these grasshopper brownies right in the slow cooker, still nestled in their foil wrappers, with extra chocolate syrup on the side so everyone can add more if they like. A scoop of vanilla or mint chocolate chip ice cream is perfect on top of a warm, unwrapped square. For a spring gathering, I like to set them on a big platter in a little stack so guests can grab and open them like tiny presents. A pot of coffee, some cold milk for the kids, and maybe a bowl of fresh berries on the table round everything out without much extra work.

Servings: 16 mini foil-wrapped brownies

1 box (about 18–19 oz) fudge brownie mix, plus water/oil/eggs as package directs (see note below)

Prepare the slow cooker: Line the bottom of your slow cooker crock with a layer of heavy-duty foil or a piece of parchment to make cleanup easier. Lightly mist the liner with nonstick cooking spray if you have it, just to keep any chocolate drizzle from sticking.

Mix the brownie batter: In a medium bowl, prepare the brownie mix according to the package directions using the water, oil, and eggs it calls for. Stir just until combined—don’t overmix. Fold in 1/2 cup of the mint chocolate chips or chopped mint candies.

Cut and prep foil squares: Tear off about 16 small squares of heavy-duty aluminum foil, each roughly 6x6 inches. You can adjust the size a bit, but you want them large enough to hold a couple spoonfuls of batter and fold closed into a little packet.

Fill the foil packets: Place a foil square shiny side up on the counter. Spoon about 2 tablespoons of brownie batter into the center. Drizzle about 1 teaspoon of chocolate syrup over the batter, then sprinkle a few extra mint chocolate chips on top. Bring the corners of the foil up and over the batter and fold to seal, creating a small, loosely wrapped square. Don’t press the batter completely flat; give it a little room to puff. Repeat with the remaining batter to make about 16 mini foil-wrapped brownies.

Arrange in the slow cooker: Stack the foil packets in the slow cooker in a loose, slightly staggered layer, like you’re building a little pile of presents. It’s fine if they overlap and rest on top of one another; just don’t pack them in too tightly so heat can circulate.

Cook the brownies: Cover the slow cooker with the lid. Cook on LOW for 2 to 3 hours, or until the brownies are set. The exact time will depend on your slow cooker. You can carefully open one packet to check— the brownie should look set around the edges and just a little fudgy in the middle.

Keep warm and drizzle: Once the brownies are done, switch the slow cooker to WARM. Leave the packets in the crock, still wrapped. Just before serving, drizzle about 1/3 cup chocolate syrup over the tops of the foil packets so you see chocolatey streaks across the little squares.

Serve the sweet surprise: Set the slow cooker on the table or counter with a spoon for scooping out the packets, and let everyone grab a warm, chocolate-drizzled foil square. The fun is in the reveal—each person opens their own packet to find the minty, gooey grasshopper brownie inside. Serve as is, or slide the brownie out of the foil onto a plate and add ice cream or extra chocolate syrup if you’d like.

For extra mint flavor, add 1/2 teaspoon peppermint extract to the brownie batter when you stir it together. If you have kids (or adults) who aren’t crazy about strong mint, use half regular chocolate chips and half mint chips so the flavor is gentler. You can also swap the mint chocolate chips for chopped mint sandwich cookies for more crunch, or use Andes mints if you want that classic grasshopper flavor. If you prefer less sweetness, skip the chocolate syrup inside the packets and just drizzle a little over the foil at the end for the look without too much extra sugar. To make these gluten-free, choose a gluten-free brownie mix and check that your chocolate chips or candies are gluten-free as well. For a slightly firmer brownie, cook on LOW closer to 3 hours; for a softer, fudgier center, start checking around 2 hours. These are best warm, but leftovers can be cooled, kept in their foil in an airtight container, and reheated in the slow cooker on WARM or in a low oven until just warmed through.