When people ask what my favorite thing to cook is, I usually say it's something that lets me stand over the stove and stir, but then allows me to leave it behind and socialize. This dish is a good example of just that. I love the act of sautéing the onions and garlic, watching the butter melt, and patiently waiting as the onions decide to brown. At just the right time, when my guests arrive and I want to step away from the stove, this casserole is ready to be poured into a pan and baked. It's a sit-by-the-fire, read-a-book, and snuggle-up kind of casserole, one that I hope you enjoy as much as I do.