I have made various types of toffee and caramel over the past year, and while the flavor comes out great, I am never successful in cutting the candy into even squares. It either seems to "re-glue" together or is too hard to cut. Is the secret in the timing of when you cut it (e.g. the amount of cooling that the candy has done)? Or is it the recipe itself? Or the cutting tools? Or something else entirely? And does the process differ for different types of candy?