Candy mixtures should boil at a moderate, steady rate over their entire surface. To guide you, our recipes suggest range-top temperatures. However, you may need to adjust the temperature on your range in order to maintain the best rate of cooking, which ensures that the candy will cook within the recommended time. Cooking too fast or slow makes candy too hard or soft. When stirring a hot candy mixture, use a wooden spoon (From Susan: I used a silicone spatula, and it was great).
The most accurate way to test the stage of the hot mixture is to use a candy thermometer. Be sure to test the accuracy of your thermometer every time you use it. To test it, place the thermometer in a saucepan of boiling water for a few minutes, then read the temperature. If the thermometer reads above or below 212°, add or subtract the same number of degrees from the temperature specified in the recipe and cook to that temperature.
Note from Susan: This is also a good idea if you live at high altitude. There are general guidelines about how many degrees to subtract for each 1000 feet of altitutde, but the best way to determine how many degrees to subtract is to test the thermometer at boiling, as suggested above.
If a thermometer is not available, use the cold-water test. Start testing candy shortly before it reaches the minimum cooking time.
Cold water test: spoon a few drops of the hot candy mixture into a cup of very cold (but not icy) water. Using your fingers, form the drops into a ball. Remove the ball from the water; the firmness will indicate the temperature of the candy mixture. If the mixture has not reached the correct stage, continue cooking and retesting, using fresh water and a clean spoon each time.
Thread stage: (230°-233°) Whe a tespoon is dropped into the hot mixture, then removed, the candy falls off the spoon in a long 2 inch-long, fine, thin thread.
Soft-ball: (234°-240°) When the ball of candy is removed from the cold water, the candy instantly flattens and runs between your fingers.
Firm-ball stage: (244°-248°) When the ball of candy is removed from the cld water, it is firm enough to hold its shape, but flattens quickly at room temperature.
Hard-ball stage: (250-266) When the ball of candy is removed from the cold water, it can be deformed by pressure, but it doesn't flatten until pressed.
Soft-crack stage: (270°-290°) When dropped into the cold water, the candy separates into hard, but pliable elastic threads.
Hard-crack stage: (295°-310°) When dropped into the water, the candy separates into hard, brittle threads that separate and snap easily.
Tips posted by Diane: