4 lb. potatoes
3 egg yolks
3-4 tbsp. butter, melted
Salt & pepper to taste
1/4-1/2 c. hot milk
Spinach Base (below)

Peel potatoes and cook in boiling water until tender. Drain thoroughly. Mash potatoes and add egg yolks, butter, salt and pepper, beating constantly. Add milk little at a time to make consistency to go through pastry bag. Fill pastry bag fitted with a large star tube. Reserve 1 1/2 cups mixture for following recipe of Spinach Base.

In a shallow lightly greased 2 quart baking dish, pipe potato mixture in swirls around sides to build a wall to pour spinach base into.

SPINACH BASE:

2 lb. spinach, washed & trim stems
1 1/2 c. reserved potato mixture
1 egg yolk
1/4 c. milk
2 tbsp. butter
Pinch salt & cayenne pepper
1 1/2 c. grated cheese, Cheddar
4 egg whites

In covered pot steam spinach just until leaves are wilted, about 4 minutes. Drain and chop spinach. Beat egg whites until stiff. Set aside.

Mix spinach, potato mixture, egg yolk, milk, butter and seasonings. Stir in cheese. Fold in egg whites. Pour in center of casserole of potatoes. Bake in 350 degree oven for 45 minutes or until spinach is puffed and potatoes have lightly browned.