These bars deliver the same comfort of a steaming mug of rich hot chocolate topped with marshmallows. They're flavorful, gooey, and the perfect treat on a wintry day.
Prepare your 8 x 8 or 9 x 9 baking pan by lining it with parchment paper or using your favorite baking pan spray. These bars tend to be a bit sticky thanks to the marshmallows and fluff, so I line my pan with parchment to make removing them easier.
Preheat your oven to 350 degrees Fahrenheit or 325 degrees Fahrenheit if using convection. Position an oven rack in the middle of the oven.
In a small pan on the stove or a small bowl in the microwave, melt the butter. As the butter melts, add the cream cheese, cocoa powder, sugars, and dry milk to a large mixing bowl.
When the butter is melted, carefully add the butter to the mixing bowl and stir to combine. The cream cheese may form small lumps, but those will be worked out as the dough is mixed. Add the eggs, vanilla, cinnamon, and salt to the mixing bowl and stir to combine.
In a bowl or a sifter, combine the flour, cornstarch, baking powder, and baking soda. Add to the mixing bowl and stir to combine. Take care not to overmix, stopping when no visible flour remains in the dough.
Add the chocolate chips to the bowl and mix until they are evenly distributed. Add the marshmallow fluff and marshmallows to the bowl and fold them into the dough. You’re not looking to incorporate the marshmallow fluff into the dough, simply to swirl it through the dough and create a ribbon of marshmallow in the batter.
Using a spatula, transfer the batter to the prepared baking pan. Spread the batter to fill the pan in an even layer. The batter may look uneven and rough at this stage, but it will even out a bit while baking.
If you’d like to add a bit of extra marshmallow fluff to the top of the pan, you can add a few spoonfuls and then use a butter knife or chopstick to swirl it into the top of the dough.
Bake the cookie bars in the preheated oven for 25 to 30 minutes or until just set on top. When fully baked, these cookie bars will begin to pull away from the sides of the pan and the top will have a somewhat dry appearance.
Appearance is the best indication of these bars being fully baked. A toothpick or skewer inserted into the middle of the pan should come out with small crumbs rather than batter attached when baked. Depending on the spot where you insert the toothpick, you may have gooey marshmallow or melted chocolate attached.
Because of their fudgy texture, chocolate chips, and marshmallow, these cookie bars may seem under baked. Resist the urge to bake them longer which will jeopardize their fudge like texture. As they cool to room temperature, they will set up nicely while remaining soft and fudgy.
Allow the cookie bars to cool to room temperature. Use the parchment paper to remove the cool bars from the baking pan, loosening any edges that are touching the pan. Cut into bars. The bars store amazingly well covered at room temperature for a week.
Notes
A Few Notes about this RecipeCINNAMON I add ground cinnamon to the homemade hot chocolate mix I keep on hand in the farmhouse kitchen all winter long. I like the warm flavor and comforting aroma it adds to the steaming cups of hot chocolate we drink after shoveling on a snowy winter’s day. If you prefer, you can omit the cinnamon from this recipe with equally delicious results.DRY MILK POWDER I like to add dry milk powder to these bars. It really adds to that creamy flavor of a delicious cup of hot chocolate. If you don’t have dry milk powder on hand, you can omit it from the recipe.I don’t recommend trying to substitute liquid milk. Even with adjustments to the dry ingredients, the texture and composition of the bars suffers. Liquid milk didn’t seem to add any discernable flavor to the baked bars.A TRICK FOR MEASURING MARSHMALLOW FLUFF Marshmallow fluff is delicious, but it can be a sticky chore to measure. I like to weigh the fluff into my mixing bowl to avoid needing to use a measuring cup.If you are using a measuring cup, spray it with a bit of cooking/baking spray before adding the marshmallow fluff. The light coating of oil makes the marshmallow much easier to get out of the measuring cup and won’t affect the dough at all.