This is really just an ingredient list and a few instructions.
Onions (regular or spring), chopped
Sharp cheese, grated
Salt and pepper to taste
Oil or butter
Cut the sweet potatoes in half lengthwise, wrap in foil, and bake until done. Scoop the flesh out into a bowl, being careful not to tear the skins, which are quite fragile. Put the skins in a baking pan. I didn't grease the pan, but it wouldn't hurt to do so.
Look at the amount of sweet potato and take a guess at how much onion and mushroom to use. For three medium sweet potatoes, I used maybe half an onion and several mushrooms. Saute the onions and mushrooms in oil or butter.
As for the spinach, it wilts down to almost nothing, so use lots of it. Add to the onions and mushrooms and saute until the spinach is wilted.
Turn off the heat and mix in a dollop or so of sour cream and some grated cheese. I add quite a bit of cheese, but this is a matter of taste (well, so is everything else in this recipe). Sharp cheddar is good, but other sharp cheeses work well, too. Add the mixture to the sweet potato flesh. Season to taste, bearing in mind that the cheese has some salt in it.
Fill the skins with the mixture and sprinkle some grated cheese on top. Bake at 350 for about 30 minutes. I usually cover them for the first 15 or 20 minutes...it depends on how moist you want them. I tried this recipe once with regular potatoes. They aren't as moist as sweet potatoes, so I think more fat and sour cream would be needed and maybe even a little milk or water...
Sorry, no picture... Maybe next time.