I wish I had a pizza from Roberta’s for every time I botched a batch of caramel sauce. Sometimes, I didn’t take the sugar far enough and it ended up pale and gloomy, like when it’s mid-March and you forget what sunshine feels like. Other times, I took it too far, burnt beyond repair. For years, I didn’t realize that you’re supposed to use warm, even hot, cream—cold cream shocks the melting sugar, causing it to seize up. Incredible, I thought. All my caramel problems, solved! Grainy caramels, no more! Except they kept turning out grainy.
Which is another way of saying, crystallized. Caramel can crystallize for a million and one reasons: because the sugar didn’t dissolve enough before reaching 238° F; because some stray sugar granules clung to the side of the pot; because you stirred too vigorously; because you just have bad luck.
In any case, crystallization comes with the territory. Think of it like a champion figure skater. She practices for hours a day, lands triples, spins like a dreidel. She’s the best in the country, even the world! But every so often, she falls. So, instead of trying to never fall—impossible—she stuffs a pillow inside her uniform, to cushion the blow. Our caramel sauce wants that tuckus pillow.
But first things first. Caramel can start two ways: One, dry, where you just add sugar to a pot or pan and start melting on the stove. Or two, wet, where you combine the sugar with water until it looks like wet sand. Many—including myself—prefer the latter because the liquid provides some insurance. It slows up the pace, gives you more control.
After you add the water, brush the sides of the pot with wet fingertips, to wash away any superfluous granules. Set on the stove over high heat. Don’t stir—let it do its thing. Everything is going great. It’s very excited and bubbly, cloudy then clear. That’s when you add the secret ingredient: acid.
Some recipes use cream of tartar. I prefer lemon or lime juice, even apple cider or balsamic vinegar. You only need a small amount, so the taste won’t be detectable. My baseline: 3 cups sugar. 1 ½ tablespoons citrus juice or vinegar. 1 ½ cups warm cream. So much salt, to taste (when cool!).
This wee amount of acid prevents any crystallization—from subtle graininess to total disasters. In other words, it leads you toward the smoothest, shiniest, silkiest caramel sauce. If you listen closely enough, you can hear the ice cream sundaes cheer.