I'm making this up as I go along. I've been craving onions but in a different way than just added to recipes. I thought roasting them would be good, but there has to be more than just the onion. So I'm adding some of my favorite things--sort of like a loaded baked potato, only it's a loaded roasted onion. The recipe serves 4 but I just made three.
Trim off the top and bottom of the onions; peel. Hollow out the onion with a small knife (save the core for another recipe). Place the onions in a 13x9-inch baking dish that has been sprayed lightly with cooking spray.
Melt butter in a medium saucepan over medium-high heat; add flour and stir until mixed. Add heavy cream little by little, stirring constantly with a wire whisk. Add salt, pepper, and minced garlic. Keep whisking until mixture thickens. Add cheese and combine thoroughly until mostly melted.
Spoon sauce into the cored onions. If you have too much sauce, spoon over and between onions.
Cover with foil and bake in a preheated 400-degree oven for 1 hour and 10 minutes. Uncover and sprinkle croutons or panko bread crumbs over tops of onions.
Continue baking, uncovered, for 10 more minutes until crumbs are lightly browned and cheese is bubbly.
NOTE: If you're a bacon lover, you could add some crumbled cooked bacon on top of the cheese before it goes into the oven.