1¾cups (420 g)smooth peanut butter(such as Skippy or Jif)
flake sea salt(such as Maldon)
1½cups (approx)mini marshmallows
Instructions
In a large mixing bowl, vigorously whisk together the brown sugar and eggs until well combined and very syrupy.
Add the peanut butter and vanilla extract and switch to a spatula or wooden spoon. Mix well until no streaks of peanut butter remain.
Scoop the mixture onto a parchment-lined baking sheet using a large cookie scoop. Take a rounded spoon, such as a tablespoon or 2 tablespoon measure, and dip the bottom in flour. Press a "well" into the middle of each cookie, flouring the spoon after each.
Place the baking sheet in the freezer for 15 minutes. Meanwhile, preheat the oven to 350° F.
Remove cookies from the freezer and sprinkle with flake salt. Bake for 10 minutes. Remove from the oven and add about 2 tablespoon of mini marshmallows in the "well" of each cookie, pressing lightly to adhere.
Bake for another 10 minutes, or until marshmallows are lightly browned and cookies are soft but set.
Allow to cool on baking sheet for 5 minutes before cooling on wire rack. Cool completely before serving. Cookies will firm up slightly upon cooling.