Make the brown butter: Cut the butter in small pieces to ensure even melting. Add the butter to a small skillet. Heat the skillet to medium heat. The butter will start to melt as the skillet heats up. Stir the butter to ensure it cooks evenly. Allow the butter to cook for about medium 3-5 minutes until the butter turns an amber color. The butter will first foam and start to pop. Then, brown bits will begin to form in the bottom of the pan. Once browned and popping slows, it is ready. Scrap the butter (and the brown bits of glory— yes, the browns bit are what you want!) into a heat-safe bowl and let rest for about 15-20 minutes.
Prepare your mix-ins: Cut the marshmallows in half (I find that cutting them the long way works better); roughly cut or break the graham crackers into small-medium bitesize pieces (remember, they will break down a little when mixing); and chop your chocolate.
Then, in a medium mixing bowl, sift the flour, baking soda, baking powder, and salt. Set aside.
Next, in a medium-large mixing bowl, add the granulated sugar, dark brown sugar, cooled browned butter, and vanilla and beat with a hand mixer for 2-3 minutes.
Then, add the egg and yolk. Beat for an additional minute. Your mixture should be shiny.
Next, add your "sifted flour mixture" into your wet ingredients and mix with a wooden spoon or rubber spatula until well combined. Be sure not to over mix.
Then, add your prepped toppings and carefully fold in your toppings until just incorporated. Be sure not to crush your graham crackers too much during this process.
Transfer the cookie dough to a fridge and let chill for at least 30 minutes to allow the flour to hydrate and obtain that brown butter and vanilla flavors (Pro tip: Allowing your dough to refrigerate for 2 hours will result in the best flavored cookie; however, 30 minutes works just fine. If you are chilling your cookies more than 30 minutes, put your marshmallows in a ziplock bag until you are ready to use).
Once your dough has chilled, remove your dough and preheat your oven to 350°F. Then, line a nonstick baking sheet with parchment paper.
Next, use a medium cookie scoop (2 tablespoons cookie scooper) to scoop the dough. With your thump, make an indention in the dough while the dough is in the scooper and insert half of a marshmallow into the indention. Once inserted, release the cookie and form Into a ball. The dough should completely cover the cookie (Pro tip: I like to place the balls back in the refrigerator for 15-20 minutes but this is optional (I find it helps the cookies hold shape, but it’s definitely not necessary as you will likely need to reshape the cookies as noted in the Notes section anyway)).
Then, place the dough onto a parchment lined baking sheet. The dough should be about 2 inches apart.
Bake the cookies at 350 degrees for 9-10 minutes and top with flaky sea salt as soon as you take them out of the oven. Use a biscuit cutter or bowl to shape the cookies into a perfect circle. Add additional graham crackers pieces if desired. Then, let the cookies rest for about 15 minutes — I know it’s going to seem like a lifetime, but it'll be worth it. We want to ensure we get the perfect texture!
Once cooled, enjoy and feel free to add a comment on my blog! Also, be sure to share your photo on instagram and tag @butterloveandsalt! We would love to see how your cookies come out!