Grandma’s Old-Time Squash Casserole

GRANDMA’S OLD-TIME SQUASH CASSEROLE
6 T. butter, divided
3 lbs. yellow squash, sliced ¼” thick
2 c. chopped onion
kosher salt
2 eggs, beaten
1 (8-oz.) container sour cream
1 c. shredded sharp cheddar cheese
½ c. shredded Swiss cheese
½ c. Miracle Whip or mayo
1 T. chopped fresh thyme
Black pepper
2 sleeved Ritz crackers, coarsely crushed
¼ c. shredded parmesan cheese

1. Preheat oven 350.
2. Melt 3 T. butter in large skillet over medium heat.
3. Add squash, onion, salt and pepper. Cook stirring often, until center of squash is just tender and liquid has evaporated.
4. Transfer to colander and set over a bowl and drain for 5-8 minutes. Discard any liquid.
5. Stir together eggs, sour cream, cheddar and Swiss cheeses, mayo, thyme, salt and pepper.
6. Gently fold in squash mixture.
7. Spoon into lightly greased 11×7” baking dish.
8. Microwave remaining 3 T. butter.
9. Toss butter with crushed crackers and parmesan cheese.
10. Sprinkle over the casserole.
11. Bake until golden brown, about 18-20 minutes.