Simple Syrup

• Hard candy starts with simple syrup, or equal parts sugar and water. For example, to make 1/4 cup of candy, you would need 2 tablespoons of sugar, 2 tablespoons of water and 1 tablespoon of cherry extract; although you start with 1/2 cup of ingredients, the water cooks out during the hardening process, leaving you 1/4 cup of hardened candy. To start the hardening process, add equal parts sugar and water to a heavy-bottomed saucepan and attach a candy thermometer. Bring the water and sugar to a boil; whisk until the water starts to boil. When you see sugar crystals sticking to the sides of the pan, dip a pastry brush in water and lightly brush the the crystals off.

Thread and Soft-Ball Stage

• Candy reaches the first primary stage of candy making -- the soft-ball stage -- when the syrup attains 235 degrees Fahrenheit. However, the syrup passes through a secondary stage, the thread stage, on the way to soft-ball stage. The thread stage ranges from 215 to 234 F, and candy cooked to this point is usually used for some types of icings, jelly and a few delicate sugar candies. As the name implies, you can pull cooled thread-stage candy into fine threads with your fingers.

  The thread stage also has its sub-stages, the pearl stage, which occurs between 220 and 222 F, and the blow stage, which occurs between 230 and 234 F. Sugar cooked to the soft-ball stage is used for fudge, fondant and Italian buttercream. To cook sugar to the soft-ball stage, let the syrup boil until it reaches between 235 and 240 F, then take the saucepan off the stove. Candy cooked to the soft-ball stage forms a pliable ball when dropped in water.

Firm-Ball and Hard-Ball Stage

• The firm-ball stage of candy hardening ranges from 242 to 248 F, and candy cooked to this point hardens into a firm, yet still malleable, ball when dropped into water. Caramel candy is perhaps the best-known example of sugar cooked to the firm-ball stage. The hard-ball stage, known for its use in making marshmallows, toffee and gummy candy, ranges from 250 to 268 F, and evidences itself by forming a hard ball that retains its shape when you take it out of water. Hard-ball candy still doesn't crack though, and compresses when you press it between your fingers. Cook the candy to between 242 and 248 F for the firm-ball stage, and to between 250 and 268 F for the hard-ball stage.

Soft-Crack and Hard-Crack Stage

• Candies cooked to the soft-crack stage include taffy and candy-apple coatings, or those that can crack when cooled but become pliable or chewy after a few seconds on the tongue. Hard-crack candy, best known for lollipops and peanut brittles, turns hard and brittle when dropped in water and cracks easily. Cook candy to between 270 and 290 F to achieve the soft-crack stage, and cook it to between 300 and 310 for the hard-crack stage.