Two-Cheese Squash Soufflé

Every serious Southern cook has his or her special crookneck squash soufflé. This is mine, in its most recent reincarnation. For years, I made the soufflé with no garlic and only sharp cheddar cheese, then decided it had to be more aggressive. Now I’m convinced that a combination of well-aged, extra-sharp cheddar (preferably Vermont or Canadian) produces the ultimate soufflé. For the right texture, do not use a food processor for this dish, and when shopping, buy only bright yellow, firm, m