Our tester Linda Pacchiano helpfully included this in her review--"You'll know when the nuts are done because the sugar turns dark, and you'll smell it and see a little smoke. You need to quickly remove the nuts to a parchment-lined baking sheet or a Silpat to stop the cooking and let them cool." Don't turn your back on the nuts, they can go from underdone to burned in the blink of an eye.