01 - Preheat oven to 350°F. Line two baking sheets with parchment paper and set aside.
02 - In a medium bowl, whisk together the gluten-free flour blend, baking soda, fine sea salt, and instant espresso powder until evenly distributed.
03 - In a large bowl, beat the softened unsalted butter, packed brown sugar, and granulated sugar using a hand mixer or stand mixer on medium speed until light and fluffy, approximately 2 minutes.
04 - Add the eggs one at a time, beating well after each addition. Mix in the pure vanilla extract until fully combined.
05 - Gradually add the dry ingredient mixture to the wet ingredients, mixing on low speed until just combined. Avoid overmixing.
06 - Using a spatula, gently fold in the chopped toasted hazelnuts, semisweet chocolate chips, and gluten-free crispy rice cereal until evenly distributed throughout the dough.
07 - Scoop tablespoon-sized portions of dough and roll into balls. Place on the prepared baking sheets, spacing approximately 2 inches apart to allow for spreading.
08 - Bake for 10 to 12 minutes, rotating pans halfway through, until edges are set and centers appear slightly soft and underbaked.
09 - Remove from oven and allow cookies to rest on the baking sheets for 5 minutes to set. Transfer to a wire rack to cool completely before serving.