Onions will keep in a cellar for close to a year. They actually seem to not last as long in a refrigerator. Make sure that they’re in a mesh bag, not something airtight.
That said, I’m not sure what to do with Vidalia onions. I never did understand what the point was of an onion that doesn’t taste like onion.
My grandmother used to cut them in half, place enough in a baking dish to fill it, top with butter and either brown sugar or maple syrup, and bake until soft. Side dish for anything. So good.
That sounds pretty good. When I put meat on the grill I often throw a couple of onions in the coals. Let them cook for about 45 minutes or so then peal away the charred bits and serve.
Make up a gigantic batch of caramelized onions and freeze them in sandwich bags. I always have some in the freezer. When a recipe calls for sweating down some onions I have a 10 minute head start. Great to defrost for toppings on burgers, hot dogs, pizzas or sandwiches. Every few weeks I do a whole bag either in the wok or the slow cooker.