This is from a Betty Crocker cookbook. One of those 'check-out counter' small cookbooks that I purchased years ago. I've made it several times and love it, and it's a good way to use up leftover ham
Cook time includes resting time..
Prepare instant potatoes according to package directions to yield the required amount.
In medium bowl combine onion, pepper, salt, if using, spinach, sour cream, cream cheese, and slightly beaten eggs; mix well.
Spread mixture into bottom of buttered dish.
Sprinkle cubed ham evenly over spinach mixture.
Top with evenly spread mashed potatoes.
Cover with foil.
Bake at 350 for 35 to 40 minutes or until mixture begins to bubble.
Remove foil, sprinkle with cheddar cheese evenly over the top.
Bake another 3 to 5 minutes or until cheese is melted.
Let rest 10 minutes before slicing.
Note: I make my potatoes slightly thinner to facilitate easier spreading. I also use a little more onion, and the salt is optional. This is a matter of taste The 4 oz of cheddar cheese should yield 1 cup of shredded cheese.