Melt a tablespoon of the butter in a large saucepan. Add the spinach and a little salt. Cook over low heat until spinach is wilted and liquid evaporates, about 3 to 5 minutes. Stir in the cream, and cook until it thickens slightly, about 1 to 2 minutes. Set aside, and cover to keep warm. Blend the eggs in a bowl, making sure the whites and yolks are completely mixed together. Add salt and pepper.
In a large heavy saucepan, melt the rest of the butter. Set the pan into a slowly simmering water bath. Pour the eggs into the pan and cook gently, stirring constantly with a wooden spoon. As the eggs thicken on the bottom and sides, scrape them so they mix into the uncooked eggs. Continue cooking until all the eggs have thickened but are still soft and moist, about 15 minutes. Add salt and pepper, if needed. Spoon the eggs onto warm plates and add a dollop of the creamy spinach to each.