Squash Casserole

6 Tables unsalted butter, divided 3 lb yellow squash, sliced thick (about 5 medium squash) 1 medium size yellow onion, chopped 2 teas kosher salt, divided 2 large eggs, lightly beaten 1 (8 oz) sour cream 4 oz sharp cheddar cheese 2 oz Swiss cheese, shredded (about 1/2 cup) 1/2 cup mayonaise 2 teas chopped … Continue reading