Beat egg whites and cream of tartar at high speed of a mixer until foamy. Gradually add sugar, beating until stiff peaks form. Add almond extract, and beat until blended. Gently fold in almond mixture.
Drop egg white mixture by level tablespoons 2 inches apart onto a baking sheet coated with cooking spray. Bake egg white mixture at 300° for 45 minutes. Remove cookies from pan; let cool on wire racks.