I need a breakfast casserole to wow my in-laws!

Hey friends. This year I will once again be going to my in-laws house for Christmas. Since they are always making us delicious dinners, my wife and I volunteer to make breakfast on Christmas morning. The one thing my mother-in-law loves more than anything is a breakfast casserole. However, I have absolute botched the last two. This is a cry for help to help me nail it this year. One thing to consider is that my MIL has is a very picky eater, so she tends to stick to the classic American flavors that you might find at say a Cracker Barrel lol. Bacon, sausage, eggs, cheese, etc. I'll also be a bit limited with cookware but there's a slow cooker, an instant pot, and the usual pots and pans (no mandolin, food processor, etc though). Does anyone have a fool-proof recipe to share with me? Thanks so much and happy holidays to you all!