Start with two cups of sugar and half a cup of water in a pan. Put over medium heat and stir until sugar s dissolved. Once it starts boiling, do NOT stir but just sort of swirl around in the pan. After 10 - 15 minutes the mixture will start to brown. Remove from heat when you get a nice nutty color.
The browning happen all at once, and so do keep your eye on things. And this stuff is incredibly hot when it's done, so be careful. When the caramel cools it will be hard. If you are making caramel sauce, stir in heavy cream right away.