Scalloped potatoes are the ultimate comfort food. Each bite of this beloved side dish offers up delicious creamy, cheesy goodness. At first glance, it's not that challenging to make. There's a fairly short list of ingredients: potatoes, cheese, cream, milk, garlic, onions, and a few spices and seasonings of your choosing. And a little bit of precision is required with the preparation, like making sure the slices of potato are of equal thickness so they cook evenly. But, other than that, most of the dish comes together in the oven, right?
It turns out that making the cream sauce takes a bit of finesse, and there's a major mistake that can be made in the timing that may leave you with lackluster results. Leaving your sliced potatoes in water for too long will rob them of their starch, and this in turn negatively affects the sauce's creaminess. It seems logical to make the potatoes in advance, especially since you might want to take out the mandoline to get those perfectly even slices. But it's when you leave the potatoes soaking in water while you work on the sauce that the dish can go awry.
Potato Starch Improves The Sauce
The question of whether or not to soak potatoes before cooking can be confusing. Some recipes actually call for the tubers to take a bath in cold water as part of their preparation. This is done to remove excess starch, which can affect how the potatoes cook. For instance, you want the surface starch removed when you're making french fries so that they brown properly and fry evenly. Excess starch can also lead to the potatoes taking on a gummy texture, and that's why some mashed potato recipes call for soaking peeled potatoes before cooking them.
Scalloped potatoes, however, actually benefit from this vegetable's starchiness. Without the starch, the sauce will not have the desired consistency. It might turn out a bit thinner and runnier than you'd like. Starch from the potatoes is essential to this dish as it helps thicken the sauce as it cooks in the oven. And it's that cheesy cream sauce that makes scalloped potatoes so delicious!
Read the original article on Tasting Table.