Mimi's Monster Mash Rice Krispies Treats

Mimi's Monster Mash Rice Krispies Treats

Posted by Mimi on Oct 20th 2026

Mimi's Monster Mash Rice Krispies Treats

Sometimes you just can't beat a classic!

We're starting with the traditional, gooey, marshmallow-filled Rice Krispies treat that everyone knows and loves. But because it's Halloween, Mimi couldn't resist adding a little spooky magic!

We're talking orange, yellow, and brown Reese's Pieces, colorful Halloween M&M's, and those adorable little candy eyeballs.

And don't forget the Halloween sprinkles! I've found some of the cutest little witches' hats, black cats, pumpkins, and ghosts.

Who knew Rice Krispies treats could dress up for Halloween?


Ingredients

  • 3 tablespoons butter

  • 1 package (10 oz.) miniature marshmallows, approximately 6 cups

  • 6 cups Rice Krispies cereal

  • ½–¾ cup Reese's Pieces or Halloween-colored M&M's

  • 2–3 tablespoons Halloween-themed sprinkles

  • Candy eyeballs for decorating

  • Optional: ½ teaspoon vanilla extract

Directions

  1. Prepare your pan. Lightly butter a 9 × 13-inch baking dish or line it with parchment paper.

  2. Melt the butter. In a large saucepan over low heat, melt the butter.

  3. Add the marshmallows. Stir gently until completely melted and smooth. Remove from heat and stir in vanilla if using.

  4. Mix in the cereal. Add the Rice Krispies cereal and gently stir until evenly coated.

  5. Add the Halloween candy. Let the mixture cool slightly so the chocolate candies don't melt. Gently fold in most of your Reese's Pieces or M&M's.

  6. Press into the pan. Transfer the mixture to your prepared pan. Using lightly buttered hands or parchment paper, press gently into an even layer. Don't pack too tightly!

  7. Decorate! While the mixture is still slightly warm and sticky, sprinkle the remaining candy, candy eyeballs, and Halloween sprinkles across the top. Press lightly so they stick.

  8. Cool and cut. Allow the treats to set for approximately 30 minutes, then cut into squares or rectangles.


Mimi's Kitchen Tip: Don't Throw Away That Butter Wrapper!

Here's one of my favorite little kitchen tricks!

Save the butter wrapper! ?

After you've added your butter to the marshmallow mixture, set that buttery wrapper aside.

When it's time to press your Rice Krispies treats into the pan, use the buttered side of the wrapper to gently press and smooth the mixture into place.

The leftover butter helps keep that sticky marshmallow goodness from sticking to your hands or utensils!

Plus, it makes spreading the mixture into the corners of your pan so much easier.

Just remember, don't press too hard! We want soft, chewy Rice Krispies treats, not marshmallow bricks!

Sometimes the best kitchen tools are the ones we were about to throw away!

A little less mess, a little less waste, and a whole lot of Mimi magic! ?


Mimi's Little Kitchen Secrets

Reese's Pieces vs. M&M's: I love Reese's Pieces because their orange, yellow, and brown colors are naturally perfect for Halloween. But Halloween M&M's work beautifully, too!

Save the decorations for the top: Those little candy eyeballs and shaped sprinkles really stand out when they're visible. I like to add most of them after pressing the mixture into the pan.

Don't squish your treats! Press them just firmly enough to hold together. Packing them too tightly makes them harder and less gooey.

Mix and match: Try a few different combinations of candy and sprinkles. No two batches have to look alike!

And remember, Reese's Pieces contain peanuts, so be mindful of allergies when sharing these treats.

Mimi's Halloween Motto: A little marshmallow, a little chocolate, and a whole lot of spooky fun!


The Spooky Fun Is Just Beginning!

Well, my little ghosts and goblins, that's a wrap on Day 1 of Mimi's Halloween Treat Adventures!

But don't put away those marshmallows, witches' hats, or candy eyeballs just yet!

We've got more frightfully delicious creations bubbling up in Mimi's kitchen, and trust me, you won't want to miss what's coming next!

Come back for more spooky treats, sweet surprises, and a little Halloween mischief!

Until next time, keep your marshmallows gooey, your treats delicious, and your spooky spirit alive!

Hugs, giggles, and a sprinkle of Halloween magic! 

— Mimi

P.S. If you hear a strange cackle coming from the kitchen, don't worry. It's just Mimi cooking up another batch of Halloween fun! Mwahahaha! ?‍♀️