Chocolate Hazelnut Gluten-Free Slice & Bake Cookies - Diamond Nuts

Ingredients

• 1-1/2 cup (156g) hazelnut flour
• 1/2 cup + 2 tbsp (75g) gluten-free oat flour
• 1/3 cup (40g) tapioca flour
• 1/2 tsp kosher salt
• 3/4 cup unsalted butter, softened to room temperature
• 1/2 cup (100g) lightly packed light brown sugar
• 1 large egg, at room temperature
• 1-1/2 tsp vanilla extract
• 4 ounces bittersweet chocolate, coarsely chopped (we used 74% dark chocolate)
• 3/4 cup (75g) finely chopped hazelnuts, toasted (chopped somewhere between powder and coarsely chopped, about the size of oatmeal)
• Optional:
• 1/2 cup finely chopped hazelnuts, toasted, for rolling
• 3 tbsp coarse sugar, such as demerara, for rolling
• Flaky salt, for sprinkling