For the cookie dough:

1. Start with the brown butter. Place diced butter in a heavy saucepan over medium heat, swirling the pan from time to time (do not stir). Once melted, it will foam up and then subside, and the milk solids will begin to separate, creating brown bits in the bottom of the pan. Swirl the pan regularly, until the butter turns a dark caramel color and a nutty aroma. Remove from the heat and pour into a glass measuring jar. Cool to room temperature, seal, then cool in the refrigerator for 1 hour, until almost completely softened.
2. Whisk the flour, baking soda and baking powder and salt in a medium bowl.
3. In a large mixing bowl, whisk together the softened brown butter and sugars for at least 2 minutes, until pale and fluffy, using an electric hand mixer. Add the egg, vanilla extract, and mix until combined.
4. Switch to a rubber spatula and add the dry ingredients to the bowl in two or three addition, mixing well. Fold in the chocolate chips only, and mix until evenly distributed.
5. Cover the bowl with plastic wrap and place in the refrigerator for 30 minutes, up to 1 hour.

For assembling the s’mores chocolate chip cookies:

1. Preheat the oven to 350°F (180°C) and line a large baking sheet with parchment paper.
2. Place 8 square of graham crackers onto the baking sheet. Top each of them with 2 cocoa feve or one large chocolate square, then add the marshmallow on top.
3. Using an ice cream scoop, scoop a large ball of cookie dough and flatten it with your hands. Then, carefully wrap the cookie dough all around the marshmallow and graham cracker. Place a chocolate feve or square on top and flatten slightly. Repeat with the other cookies.*
4. Bake for about 12 minutes, or until the center are soft and melty while the edges are golden and slightly crispy. The cookies will be very tall in the oven at first but will deflate while baking. Remove from the oven and sprinkle a few additional chocolate chips onto the cookies.
5. Leave on the countertop for about a minute, then use a round cookie cutter (or a bowl) slightly larger than the cookie to scoot them into a perfectly round shape and give it some puffy craters on top. Sprinkle with sea salt. Cool on the baking sheet for 10 minutes, and transfer the cookies to a cooling rack, or eat them immediately while still warm and oozing with marshmallows and melty puddles of chocolate.