Use a Plate to Check If Your Sauce Is Ready.
If you’ve ever cooked gravy, or any sauce, or similar food that has a thickener added, you know that it works completely differently when you take it out of a hot boiling pot and place it on a plate. Gravy, jams, and many sauces thicken as they cool, and it can be difficult to tell when they are “ready” while they are simmering. Instead of relying on how they cover the spoon, pour some onto a cold plate or plate at room temperature and watch how it behaves. (If you like the spoon trick, great, but I always get stuck on whether the spoon is covered enough and I just stare at the spoons for too long.)
When choosing a plate temperature, think about how you are going to store or serve what you are cooking. Jam makers test their produce on a cold plate to see how thick they thicken, which makes sense because jams are usually stored in cold conditions. Put some jam on a plate that has been in the freezer for five minutes, then hold the plate upright. If the jam comes down slowly, then it’s done . (You can also put the jam on a plate and then put the plate in the freezer . If it hardens after a few minutes, you should be fine.)
For sauces and gravies, the plate doesn’t need to be so cold. Both are usually served on plates at room temperature (or slightly lukewarm), so it makes sense to test them on them rather than something chilled. Once you think your gravy or sauce has reached its “end point,” take a spoon and pour it onto a plate at room temperature, let it sit for a few seconds, and watch it behave. If it’s a little thinner than you’d like, cook it longer and then repeat until it thickens to your liking.