Frankenstein Rice Krispie Treats Recipe

Frankenstein Rice Krispie treats are green marshmallow cereal bars with dipped chocolate hair, candy eyes, a piped stitched mouth and little bolts on the sides. One 9×13 inch pan makes 12 monsters in about 55 minutes, and most of that is the base cooling on the counter. The trick is to tint the warm marshmallow with gel color before the cereal goes in, then press the mixture lightly so the bars stay soft.

What One Pan of Monsters Takes

• Base: 6 cups Rice Krispies, one 10 oz bag of mini marshmallows, 3 tablespoons unsalted butter, ½ teaspoon vanilla (optional), green food coloring
• Hair: 1 cup semi-sweet or milk chocolate chips melted with 1 tablespoon coconut oil or shortening
• Faces: candy eyes, black writing gel or melted chocolate in a piping bag, mini marshmallows or Tootsie Rolls for bolts
• Pan and cut: a greased 9×13 inch pan, cut 3 rows by 4 for 12 rectangles about 3 by 3¼ inches
• Time: 15 minutes prep, 10 minutes on the stove, 30 minutes cooling
• Keeps: 3 days in an airtight container at room temperature

Melting the Marshmallows Without Making Hard Bars

Melt the butter in a large saucepan over medium heat, then add the marshmallows and stir the whole time. Turn the heat down if they start to catch. Take the pan off the stove the moment the last lump disappears and the mixture looks smooth and glossy. Marshmallow that keeps cooking turns into candy, and that is why some cereal bars are crunchy and hard to bite a day later.

Fresh marshmallows matter here too. An old, half dried bag melts into stringy clumps instead of a smooth sauce, and those clumps never coat the cereal evenly.

Getting the Frankenstein Green

Stir in the color a few drops at a time while the marshmallow is still on the heat, before any cereal goes in. Gel color gives a strong green with very little liquid. Liquid color works, but you need more of it, and the extra water makes the base a little softer. The white cereal lightens everything, so aim one shade darker in the pot than you want on the tray. A drop of yellow pushes it toward a lime monster.

Stir in the vanilla now if you are using it. Then take the pan off the heat and fold in the 6 cups of cereal right away, scraping the bottom so no pale patches are left.

Pressing and Cutting the Green Base

Tip the mixture into the greased pan and level it with a buttered spatula or a sheet of wax paper. Press only until the top is flat and the corners are filled. Packing it hard squeezes the air out of the cereal and gives you a dense, chewy brick.

Let it cool completely at room temperature, about 30 minutes. Cut too early and the edges sag and smear. Turn the block out onto a board, cut 12 even rectangles with a sharp knife, and set them on a parchment lined baking sheet so the chocolate has somewhere to drip.

Hair, Eyes, Stitches and Bolts

Microwave the chocolate chips with the coconut oil in 30 second bursts, stirring after each one, until smooth. Dip the top edge of each rectangle about ½ inch into the chocolate, let the extra drip back into the bowl, and stand it on the parchment.

Wait a minute or two before the eyes go on. Hot, thin chocolate lets them slide down the face, and fully set chocolate will not grab them at all. When the hair has thickened and lost its runny shine, press two candy eyes in just below the hairline so they look like they are peeking out.

Pipe a stitched mouth with black writing gel or melted chocolate. High eyebrows make a friendly cartoon monster, and a scar line near one eye makes him look rougher. Push half a mini marshmallow or a small piece of Tootsie Roll into each side at the base for the neck bolts. For Frankenstein pops, push a lollipop stick up into the bottom of each bar.

Leave them at room temperature until the chocolate and gel are firm to the touch, or give them a few minutes in the fridge if the kitchen is warm.

Coconut Oil, Shortening or Butter in the Chocolate Hair?

Coconut oil is my pick. One tablespoon in 1 cup of chips gives a thinner dip, a glossy finish and hair that sets firm but still bites cleanly instead of cracking off the cereal. Shortening does the same job with no coconut flavor. Butter thins the chocolate as well, but the hair sets duller and softer at room temperature. Plain melted chocolate with nothing added sets stiff and tends to snap away from the bar. Skip margarine, which can make the chocolate thick and grainy.

When Frankenstein Treats Turn Hard, Streaky or Messy

• Bars are hard the next day: the marshmallow cooked too long or too hot, or the mixture was packed down. Melt on medium to low heat and press lightly next time.
• Green is streaky or patchy: the color went in after the cereal. Always tint the melted marshmallow first, then fold in the cereal.
• Chocolate turned thick and dull: it got too hot. Stir in another teaspoon of coconut oil off the heat rather than microwaving it longer.
• Hair slides off the top: the bars were still warm when dipped. Let the base cool the full 30 minutes before cutting and dipping.
• Eyes fall off: the chocolate set before they went on. Dab a dot of melted chocolate on the back of each eye and press it in place.

Planning Frankenstein Treats for a Halloween Party

You can make and decorate the whole tray the day before. Once the chocolate is firm, store the treats in an airtight container at room temperature with a square of parchment between layers so the hair does not stick to the bar above. They keep for up to 3 days. The fridge firms the chocolate on a warm day, but long storage in there dries the cereal out.

For a bigger party, make two separate batches in two 9×13 inch pans for 24 treats rather than one oversized pot of marshmallow, which is hard to stir evenly. Set up the decorating like a little assembly line: dip all the hair first, then do every pair of eyes, then the mouths, then the bolts. Kids are good at the eyes and bolts.

Frankenstein Treat Questions From Party Planners

Can I use regular marshmallows instead of mini?

Yes. Use 10 ounces of regular marshmallows, about 40 large ones. They take a minute or two longer to melt, so keep the heat at medium and keep stirring.

How many treats does a 9×13 pan make?

Twelve rectangles about 3 by 3¼ inches. For smaller bites, cut 24 squares and use one candy eye each for a cyclops monster.

More Halloween Treats for the Same Table

Since the cereal base is already out, Rice Krispie brains are a gory partner for these. For something baked, mummy brownies and Halloween brownies cut from one pan just like these bars. Halloween finger cookies and Halloween cake pops give the table a creepier look, and Halloween strawberries add something fresh. For the whole spread, see my Halloween party snacks.