3 squash creamed spinach gratin Recipes

fresh spinach , stems discarded, or 3 (10-oz) packages frozen leaf spinach, thawed, unsalted butter plus additional for greasing pan, chopped onion (1 small), garlic cloves, minced, salt, black pepper, freshly grated nutmeg, heavy cream, butternut squash (2 large), peeled, quartered, and seeded, grated parmigiano-reggiano (1/4 cup)

fresh spinach , stems discarded (or 3-4 packages frozen leaf spinach, thawed-10 oz.), unsalted butter (plus additional for greasing pan-or use cooking spray to grease the pan), chopped onion (1 small), garlic cloves, minced, salt, black pepper (lemon pepper is good too), freshly grated nutmeg, heavy cream (or use 1/2 and 1/2 or use evaporated milk), butternut squash, peeled, quartered, and seeded (2 large), parmigiano-reggiano cheese, finely grated, gruyere cheese (optional)