Twiks Bars Ingredients For the shortbread crust: 12 ounces (3 sticks) cold unsalted butter, diced, plus more for greasing the baking dish 15 ounces all-purpose flour 3 ounces sugar ¾ teaspoon kosher salt For the caramel layer: 10 ounces sugar 4 ounces water 3 ounces heavy cream 4 ounces (1 stick) unsalted butter, diced