Gather a large saucepan, a spatula, and line an 8-inch square dish with parchment paper.
Place the marshmallows in the saucepan and melt them over low heat, stirring constantly until the mixture is smooth, glossy, and fragrant—about 3 minutes. You'll hear a gentle bubbling and see the marshmallows turn into a gooey pool.
Add the butter to the melted marshmallows, stirring until it melts completely and the mixture becomes shiny and fragrant, about 1 minute. This adds richness and helps everything come together.
Pour the crispy rice cereal into the marshmallow mixture. Gently fold the cereal in with your spatula until it’s evenly coated and the mixture looks sticky and well combined, with a slight puffed appearance and a sweet aroma filling the air.
Scoop the mixture into the prepared dish and use the back of your spatula or a piece of parchment to press it down gently, spreading it into an even layer about 1 inch thick. Press softly to avoid squishing all the air out but firmly enough that the mixture sticks together.
Let the mixture cool at room temperature for 20–30 minutes until firm, or refrigerate for about 10 minutes for a quicker set. You’ll notice it becomes less sticky and more solid, with a golden hue on top.
Once cooled and firm, use a sharp knife to cut into 1-inch squares. Wipe the knife clean between cuts for neat edges. You’ll hear a satisfying crunch as the knife slices through the crispy bites.
If desired, melt the chocolate chips gently and drizzle over the bites for an extra touch of sweetness and shine. Let the chocolate set for about 10 minutes before serving.
Enjoy these crunchy, sticky bites immediately or store in an airtight container at room temperature for up to 3 days for maximum freshness and crunch.
