Click. Extra tips: Use a deep pot. That way, when it rises, it won't overflow. If you don't know what firm ball(310 degrees F, very hot!) is: Make a cup of cold water. It must be cold. Then, put some of your mixture in it, it should form brittle, hard threads. Before this stage it will be soft ball, where it forms a soft shape, still able to be moulded into a different shape. When/if you eat it, it should be chewy.
Credit to whomever the heck made this recipe.