Preheat oven to 350 F = 175 C.

Prepare a baking sheet by lining with parchment paper

In a large bowl, whisk together flour, sugar, baking powder, and salt.

With a hand mixer, beat in eggs and vanilla until combined.

Add almonds and almond extract and beat until combined.

Divide dough in half and transfer to a baking sheet.

Form each half into a log of about 2 1/2" wide and 3/4" tall.

Bake until dough is firm but gives slightly when pressed (20 to 25 minutes), rotating sheet halfway through.

Let cool on sheet on a wire rack for 20 minutes.

Meanwhile, prepare 2 baking sheets by lining with parchment paper.

With a serrated knife, cut the log into 1/4" slices on the diagonal.

Arrange, cut side down, on 2 baking sheets.

Bake until biscotti are crisp and golden, about 15 minutes; rotate sheets and flip biscotti halfway through.

Let cool on sheets on wire racks.