Preheat your oven to 375°F (190°C).
Yes, preheating matters. Thinking you can skip it? Rookie mistake.
Crush the Oreos.
Toss them in a zip-top bag and smash them with a rolling pin, or pulse them in a food processor. Keep some chunks—texture is your friend.
Layer the Oreos in an oven-safe dish.
Press them lightly into the bottom. This is your crunchy foundation.
Add the chocolate.
Sprinkle chocolate evenly over the Oreos. If you’re using butter, dot it over the chocolate for extra meltiness.
Top with marshmallows.
Go generous. Sparse marshmallows are just sad.
Bake for 8–10 minutes.
Watch closely. You want melted chocolate and golden marshmallows, not a smoke alarm situation.
Serve immediately.
Grab dippers, gather people, and dive in while it’s still warm and gooey.