Preheat the oven to 325°F (160°C) and line a large baking sheet with parchment paper.

In a large mixing bowl, whisk together the almond flour, granulated sweetener, baking powder, and sea salt until no lumps remain.

In a separate small bowl, beat the eggs with the vanilla and almond extracts until fully emulsified.

Incorporate the wet ingredients into the dry ingredients using a spatula until a thick, sticky dough forms.

Fold in the toasted slivered almonds until evenly distributed.

Transfer the dough to the prepared baking sheet and shape into a rectangular log approximately 10 inches long and 3 inches wide.

Bake for 25 minutes until the log is firm and the edges are lightly golden brown.

Remove from the oven and allow the log to cool for exactly 15 minutes to stabilize the crumb structure.

Reduce the oven temperature to 300°F (150°C).

Using a sharp serrated knife, cut the log into 3/4-inch thick diagonal slices using a gentle sawing motion.

Arrange the slices cut-side down on the baking sheet and bake for 10 minutes.

Flip the biscotti to the other side and bake for an additional 10 minutes until toasted and dry.

Transfer the biscotti to a wire cooling rack; they will reach maximum crispness once completely cooled.