Preheat oven to 300°F. Line two baking sheets with parchment paper.

In a large bowl, beat eggs and sugar together until airy. Mix in almond extract.

In another bowl, mix together flour, baking powder, and salt, then carefully stir into egg mixture until incorporated.

Fold in almonds. The dough will be somewhat wet and sticky.

Divide dough in half onto baking sheets. Pat dough into a flat rectangular oval, skinnier for smaller biscotti.

Bake for 50 minutes to 1 hour, rotating the baking sheets halfway through. Let cool for 5 minutes.

Using a serrated knife, cut on the short end into 1-inch-thick slices, and place slices cut-side up on baking sheets.

Bake for an additional 20-30 minutes, flipping cookies over halfway through.

Let cool completely before storing in airtight containers.