01 -
In a large mixing bowl, beat the softened butter, granulated sugar, and light brown sugar until light and fluffy, approximately 3 to 5 minutes.
02 -
Add the egg and vanilla extract to the butter mixture and beat until fully incorporated.
03 -
In a separate bowl, whisk together the all-purpose flour, baking soda, and sea salt.
04 -
Gradually add the flour mixture to the wet ingredients in three additions, mixing until just combined after each addition.
05 -
Gently fold in the white chocolate chips and cereal marshmallows, taking care not to break the marshmallows.
06 -
If desired, chill the dough for 15 to 30 minutes for improved texture.
07 -
Form dough into balls using a 1.5 tablespoon scoop or by hand, and arrange evenly on a parchment-lined baking sheet.
08 -
Bake in a preheated oven at 350°F (177°C) for 8 to 10 minutes, removing when edges are just turning golden for a softer texture, or slightly longer for a crispier cookie.
09 -
Let cookies rest on the baking sheet for 2 to 3 minutes after removing from the oven, then transfer to a wire rack to cool completely.