I got inspired by this recipe and modified it to fit a B Nomad:

http://artofhacking.com/aohfood/60000/60072-sweetpotatocheeseonioncasserole.htm

  Title: Sweet potato~ cheese & onion casserole
Categories: African, Vegetables, Vegetarian
      Yield: 4 Servings

      1 lb Sweet potatoes; peeled &
           -sliced thinly
           -a little water or stock
      1 tb Margarine
      1 lg Onion; sliced thinly into
           -circles
      1 c  Cheese; grated
    1/2 ts Chili powder
           -Salt and Pepper

  Preheat oven to 350F/180c/gas mark 4. grease an oven proof dish and
  line it with the sweet potato slices. pour in just enough water or
  stock to coat the base of the dish evenly and then dot with margarine
  amongst the layers of potato. arrange the onion circles on top of the
  the sweet potato and finish up with the cheese. Sprinkle on the chili
  powder, salt & pepper. Cover the dish and cook for 1 hour, removing
  the lid for the last 15 minutes to brown. Serve hot as a main dish.

I skipped the water, margarine, and chili powder and used:

Sweet potato
Vidalia Onions (sweet onion)
Baby Spinach
Portabella Mushrooms
batch 1 - Jarlsberg Cheese; Grated Parmesan Cheese on top
batch 2 - Smoked Gouda

I greased my pans with olive oil and lined the pan with sweet potato slices and put spinach, onion, and mushroom on top. Salted in between the layers and put cheese.

You do not need to use water if you use spinach, onions, and mushrooms since they have water in them.

I used 2 sweet potatoes and 4 or 5 small onions - ended up filling up a 9X13 pan AND a 2 quart casserole dish!

I will have plenty of leftovers since I live alone. This forced me to make my own "frozen food".

That sounds so good! I can make that for my Nomad hubby and freeze leftovers.  Thanks for showing how you made it compliant.

Glad to be of help.

For multi-layered casseroles, you can go up to 375 and bake it for about 1.5 hours. Cooking time depends on the thickness of the casserole.

Thanks, PP...

It sounds really good.  I'll have to make this.

It does sound really good!!

Except I don't eat onions and I'm on a no dairy trip right now.  I absolutely love onions and hope to have them again someday.  Cheese too.  

So, what I'm saying is:  Savor it for me!!!  

@ABJoe - Enjoy!
@JJR - I hope you can add your "beloved" onions and dairy, soon. I definitely will! Praying that your gut will heal so you can have onions and dairy again.

Thank you!!!  That is so nice of you!!!  I do miss them onions.  I don't know what it is, but it came up as a high reaction on my IgG food antibody test and when I eat them, it seems to provoke my heart arrhythmia to happen.