As amazing and decadent as ooey-gooey fudge is, if you’re making the old-fashioned kind, there are a few necessary steps to give it that smooth, creamy, soft-solid consistency it’s known for. Old-fashioned fudges do not use marshmallows or condensed milk to help them set and solidify, so they’re trickier to get right.
To harden fudge that’s too soft, you need to reheat and re-beat it to the right consistency.
The soft-ball stage is the sweet spot when cooking fudge. At this point, the sugar concentration is roughly 85 percent, and the candy forms a soft, malleable ball when dropped in cold water. To get there, cook fudge to 235 to 245 degrees Fahrenheit. While you can go ahead and drop it in cold water as a test, a candy thermometer is the most accurate gauge for whether it’s ready to cool and stir.
Crystals in Fudge
Once the fudge has reached the soft-ball stage, cool it to 130 degrees Fahrenheit, slowly and gradually. Trying to speed up the cooling process by putting the pot in the fridge or setting it in an ice-water bath can cause crystallization and give the fudge a grainy texture.
Add any extracts for flavor, then stir continuously for roughly 20 to 25 minutes. If you don’t stir hard or long enough, the fudge won’t be properly mixed, and crystallization may occur at this stage, too.
If all goes well, the fudge should have its signature creamy texture and matte appearance.
Redo Soft Fudge
If the fudge doesn’t set after heating and stirring, but it doesn’t have a grainy texture, that means it’s been cooled properly but wasn’t heated to a high enough temperature while cooking.
To reset soft fudge, return it to the pot and add in 1 to 1 1/2 cups water per batch of fudge. Reheat the fudge until it reaches the soft-ball stage. Repeat the steps of cooling and stirring, but there’s no need to add extra seasoning.
Soften Hard Fudge
Fudge that’s too hard once it’s set can sometimes be softened. It might have been stirred too long, causing the sugar crystals to become too fine, or overcooked, as the firm-ball stage for sugar is only 5 degrees Fahrenheit higher than the soft-ball stage—between 245 and 250 degrees Fahrenheit.
To soften hard fudge, warm it up in a pan, add 1 cup water, and recook and re-beat the fudge. Take care to heat it to no more than 245 degrees Fahrenheit. Stop beating as soon as it becomes difficult to stir.