In a large bowl, stir together the almond flour, sugar, and salt. Add the egg whites, almond extract, and vanilla extract, then mix until a thick, sticky dough forms.

Scoop 2-tablespoon portions of dough, roll into balls, then coat each ball in the sliced almonds. Place on a parchment-lined baking sheet about 2 inches apart and flatten slightly.

Preheat the oven to 350°F (180°C). Bake for 12 to 14 minutes, until the edges are just turning golden and the tops look dry and set.

Let the cookies rest on the hot sheet for 5 minutes, then transfer to a wire rack to cool completely before serving.