Marinated Roasted Onions with Madeira Sauce

Oftentimes, the rule with onions is “low and slow is the way to go” because low heat allows the onion to release its natural sugars and become amazingly tender. But in this recipe, we utilize a high heat fast caramelization process which is made possible by using the top and bottom heating elements of the Anova Precision Oven. Cooking onions on high heat for a short time will not yield an amazingly complex onion flavor, so we use a marinade to enhance the dish. We further help the onions achieve perfect doneness by slicing them crosswise instead of roasting them whole. The result is a tender but caramelized onion that is sure to be a memorable side dish your guests won’t forget. A little splash of Madeira wine fortifies the cooking liquid, giving the onions another layer of sweetness. You can substitute any sweet fortified wine such as Sherry, Marsala, Port, or even Sweet Red Table wine depending on what you have on hand. These onions will surely make you cry tears of joy once you’ve had it.