Place 1 large head of cauliflower in pan with water. Bring to boil; cover and turn off heat. Let set for 15 minutes. Place drained head in casserole dish. Mix 1 can cream of shrimp soup, 1 (8 ounce) container of soft cream cheese, and 8 ounces shredded cheddar cheese. Pour over cauliflower head and cover. Bake for 1 1/2 hours at 350 degrees.