Begin by preheating your oven to 350°F. Line two baking sheets with parchment paper or silicon baking mats. Spread the hazelnuts evenly on one of the baking sheets and toast them for 5 to 7 minutes.

Break chocolate into pieces no larger than a lima bean. You can either chop the chocolate in a food processor fitted with a steel blade using on-and-off pulsing, or place it in a plastic bag and gently crush it.

In a saucepan over low heat, melt the chocolate and butter together, stirring frequently until the mixture becomes fully melted. Once melted, remove the pan from the heat and set it aside for 5 to 7 minutes to cool. Alternatively, you can use microwave oven.

In a mixing bowl, whisk together the rice flour, cocoa, cornstarch, baking powder, xanthan gum, and salt until well mixed.

In another mixing bowl, beat together the eggs, granulated sugar, Frangelico, and vanilla extract at high speed using an electric mixer for 1 minute. Then, beat in the cooled chocolate mixture followed by the dry ingredients. Carefully fold in the toasted hazelnuts and bittersweet chocolate chips.

Drop the dough by 1-tablespoon portions onto the prepared baking sheets, leaving about 1½ inches of space between each cookie. Bake for 10 to 12 minutes, or until the tops of the cookies are dry and set.

Allow the cookies to cool on the baking sheets for 2 minutes before transferring them to a wire rack to cool completely.

• For a delightful twist, add 1 tablespoon of instant espresso powder to the chocolate and butter mixture for a mocha flavor.
• Enhance the dough with ½ teaspoon of ground cinnamon for a warm.
• For a different flavor profile, swap out the bittersweet chocolate chips for white chocolate chips.