Equipment Needed
- 8×8 inch or 9×9 inch square baking pan
- Parchment paper
- Medium mixing bowl
- Small saucepan
- Spatula
- Measuring cups and spoons
Step-by-Step Instructions
My process always begins with the pan. I line my 8×8 inch pan with a sheet of parchment paper, leaving some overhang on two sides. This isn’t just for easy cleanup; it’s the secret to lifting the entire slab of bars out in one perfect piece for clean slicing later. I learned this the hard way after trying to cut bars directly in the pan—it was a crumbly, messy affair. Once my pan is prepped, I make the graham cracker base. In a medium bowl, I combine the graham cracker crumbs, sugar, and salt. I pour in the melted butter and stir until every crumb is coated and the mixture holds together when I pinch it. It should feel like damp sand.
Next, I pour the crumb mixture into my prepared pan. Using the bottom of a flat glass or a measuring cup, I press it down firmly and evenly into every corner. This firm press is non-negotiable; a loosely packed base will fall apart when you try to pick up a bar. I really put some weight into it, going over the entire surface several times until it’s compact and smooth. Then, I sprinkle the 1 1/2 cups of chocolate chips evenly over the crust, followed by 3/4 cup of the mini marshmallows. I save the last 1/4 cup for the top. The sight of those chocolate chips and fluffy marshmallows nestled on the golden crust is already so promising.
Now for the “glue” that holds everything together. In my small saucepan, I combine the sweetened condensed milk and vanilla extract. I warm it over medium-low heat, stirring constantly, just until it’s hot to the touch and begins to steam—about 3-4 minutes. You don’t need to boil it, just warm it thoroughly. This warm milk will help melt the chocolate and marshmallows slightly, binding the layers. I carefully pour the warm milk mixture evenly over the top of the chips and marshmallows in the pan, trying to cover as much surface area as possible. (See the next page below to continue…)