01 -
Start by preparing the crunchy base. In a bowl, mix the melted butter with graham cracker crumbs until all crumbs look coated and blend together. If you pinch the mixture and it crumbles, drizzle a little more butter. Then press this mix into the bottom of an 8×8-inch pan with something flat, like the back of a measuring cup. Set aside.
02 -
Melt together your chocolate chips and condensed milk in a microwave-friendly bowl. Heat for 30 seconds, stir well, and repeat if needed until it’s silky and smooth. Pour this mixture over the crust you made earlier and use a spatula to spread it evenly all the way to the pan’s edges.
03 -
Before your chocolate sets, scatter marshmallows across the top like a blanket, making sure they’re spread out. Sprinkle optional milk chocolate chips randomly over the marshmallows for extra gooeyness. Don’t worry—the marshmallows stick as the chocolate cools!
04 -
Put the pan in the fridge to chill for about 2 hours, or until everything’s set and firm. If you want to try and speed it up, pop it in the freezer for around 45 minutes, though slower fridge-setting gives a better texture.
05 -
Once it’s cooled and firm, take it out and cut into squares. I like to warm the knife under hot water and dry it before slicing each time for neat shapes. Pull the bars out of the fridge a bit before serving so they’re softer to eat. These make great snacks at parties or outdoor gatherings.