Nut Bar

Two ingredients and one technique: caramel poured over nuts. Everything depends on how you handle the melted sugar.

• The hinge: dry caramel"Melted as for Peanut Nougat" means sugar melted alone in a heavy pan over moderate heat, with no water added, stirred as it liquefies. The book gives no thermometer reading: go by colour, and take it off the heat as soon as it is an even amber, since sugar carried much past that turns bitter and will taste scorched in the finished bar.
• One pound sugarAbout 2 1/4 cups granulated. Weigh it if you can, since the ratio of caramel to nuts is what makes the bars hold together rather than crumble.
• CastaneasCastanea is the chestnut genus, so the first option is chestnut meats, sold cooked and peeled in vacuum packs today. They are soft and starchy next to walnuts or almonds and give a much less crisp bar; either of the other two nuts is the safer choice.
• Warm the nutsNot in the original, but worth doing: warm the nut quarters gently in the buttered pan while the sugar melts. Cold nuts chill the caramel on contact and it can stop flowing before it has coated them.
• Pan sizeThe recipe specifies only a "shallow pan"; something on the order of an 8-inch square or a quarter sheet suits this quantity. A thin layer sets faster and cuts more cleanly than a deep one.
• Marking in barsScore the surface with an oiled knife while the caramel is still pliable, roughly three to five minutes after pouring. Wait until it is fully hard and it will shatter along its own lines instead of yours.
• Yield and keepingA pound of sugar with 1 1/3 cups of nuts makes something over a pound of candy. Store airtight with parchment between layers; humidity makes caramel tacky.