Start by warming your oven to 325°F (160°C). Grab a baking sheet and line it with parchment paper for effortless cleanup.
In a food processor, add the almond flour, ground flaxseed meal, sweetener, coconut flour, gelatin powder, baking powder, and salt. Give it a few quick pulses until everything is perfectly combined.
With the food processor running on low speed, slowly pour in the melted coconut oil, egg yolk, and almond extract. Continue mixing until the dough cleverly comes together into a ball.
Stop the processor, gently scrape down the sides of the bowl, then add the ⅓ cup of chopped almonds. Pulse just briefly—enough to evenly incorporate the almonds into your lovely dough.
Transfer the dough onto your prepared baking sheet. Gently shape it into a neat rectangular log, approximately 4 x 10 inches. Pop it into the preheated oven and bake for 20 minutes until it's just lightly golden.
Carefully remove the log from the oven. Using a large, sharp knife, press down to cut it into 10 even slices. Gently wiggle the knife back and forth between the slices to create small gaps. Reduce your oven's temperature to 225°F (107°C). Place the sliced biscotti back in the oven and bake for an additional 40 minutes to crisp them up beautifully.
Once baked, let your biscotti cool completely on the baking sheet. This step is super important as they firm up significantly as they cool, ensuring that perfect biscotti texture.
If you're adding a topping, gently turn each cooled biscotti on its side. Drizzle and spread the melted sugar-free chocolate onto the bottom half. Flip them upright, then drizzle chocolate on the top and sides, and sprinkle with the extra 2 tablespoons of chopped almonds. Remember to drizzle rather than dip, as these are delicately delicious!