1/2cuppeanut butter chipsyou may have some leftover
Instructions
Cut marshmallows in half and place on a wax paper lined plate in the freezer.
In a medium bowl, whisk together flour, salt, baking soda, and cornstarch. Set aside.
With an electric mixer in a large bowl, beat the softened butter until creamy.
Add brown sugar and beat until completely combined. Add egg and beat until combined.
Add peanut butter and vanilla and beat until combined.
With the mixer at low speed, add the flour mixture incorporating until no traces of flour remain. Do NOT add peanut butter chips, you will use them in a later step, before the cookies go into the oven.
Use a large cookie scoop (3 tablespoons), to portion out all cookies onto a wax paper lined plate or tray. Place dough balls into the refrigerator for 30 minutes.TIP: The dough is sticky at room temperature. Chilling the dough makes it much easier to handle.
Meanwhile, preheat oven to 350 F. Line insulated baking sheets with parchment paper.
Remove dough balls from refrigerator. Using gloved hands, slightly flatten dough ball and place half a frozen marshmallow into the center. Press in in gently and gather the dough up around the sides of the marshmallow, carefully pressing the dough together to completely close in the marshmallow.TIP: Since the melted marshmallow will seep out, you want the marshmallow to be closer to the top of the cookie rather than the bottom.
NOTE: It’s best to keep the marshmallows frozen for as long as you can. Only bring out enough for the batch you are putting in the oven. Keeping them frozen will keep them from melting too quickly while the cookie bakes.
Place some peanut butter chips into the palm of one hand. I found that 9 chips per cookie (placed close together) was the magic number.
Gently press the top of the cookie into the chips in your palm, the chips will stick. The cookies spread when they bake, so the closely placed chips will spread out too.
Bake for 10-12 minutes. Ours were perfect in 10 1/2 minutes.
Remove from oven and cool on pan for 10 minutes. These cookies are delicate while hot, so trying to move them too soon will cause your cookies to fall apart.
Carefully transfer to wire cooling racks to cool completely.
Video
Notes
The first time you make these I highly recommend only putting 2 cookies in the oven. Watch them carefully. Mine were done at 10 1/2 minutes. When I baked for 11 minutes the marshmallow melted too much and became clear and bubbly. You want the marshmallow to melt, but remain puffy and white. Once you establish the perfect time for your oven, go ahead and bake full batches!
I found it a lot easier to dot the peanut butter chips on top rather than mixing them into the dough. If mixed into the dough, it makes it more difficult to form the cookie dough around the marshmallow.
Freezing the marshmallows will help them from melting and seeping out of your cookies as much, though a little bit of seepage is to be expected. The trick is to wrap your marshmallow closer to the top of the cookie dough ball rather than the bottom. Marshmallow creme isn't ideal in this recipe as it's already thin and gooey and will be difficult to work with, I would recommend sticking to actual marshmallows here.