1) Preheat oven to 350 degrees
2) Spread single layer of artichoke hearts to cover bottom of baking dish. Wring all water out of spinach, layer over artichoke hearts. Finish with another layer of artichoke hearts.
3) Soften cream cheese and butter in microwave until spreadable. Spread evenly over top of casserole. Finish with grated Parmesan cheese.
4) Cover with aluminum foil and cook for 45 minutes. Remove cover and cook for 15 more minutes, until top is golden brown. If the top doesn’t brown, you can turn on the broiler for a minute or two, but watch carefully, to avoid burning.