The recipe for toffee is incredibly simple, comprised mostly of sugar and butter. Is there an ingredient or something particular to the cooking process that distinguishes between a toffee that has a clean, crunchy, almost flaky texture and the kind that is slightly stickier and has a tendency to get stuck in your molars?
It nearly all comes down to cooking time and temperature. You can use the exact same ingredients and come out with a differently-textured batch every time. The rule of thumb I use is to cook it until it’s about the color of a brown paper bag and is smoking a bit (but not too much!) The longer you cook it, the harder it will be.
Yup. It’s pretty much the difference between 295F (borderline soft-crack/hard crack) and 310F (hard crack).