Heat oven to 350°F. Spread hazelnuts in ungreased shallow pan. Bake uncovered about 10 minutes, stirring occasionally, until golden brown; cool.
In large bowl, beat sugar, butter, almond extract, vanilla and eggs with electric mixer on medium speed, or mix with spoon. Stir in flour, baking powder and baking soda. Stir in hazelnuts. Place dough on lightly floured surface. Gently knead 2 to 3 minutes or until dough holds together and hazelnuts are evenly distributed.
Divide dough in half. On large ungreased cookie sheet, shape each half into 10x3-inch rectangle, rounding edges slightly.
Bake about 25 minutes or until center is firm to the touch. Cool on cookie sheet 15 minutes; move to cutting board. Using sharp knife, cut each rectangle crosswise into 1/2-inch slices.
Place 20 slices, cut sides down, on ungreased cookie sheet. Bake about 15 minutes or until crisp and light brown. Immediately remove from cookie sheet to cooling rack; cool. Cool cookie sheet 5 minutes; repeat with remaining slices.