Step 1

Preheat oven to 350°F. Butter

Step 2

a 9-by-13-inch baking dish. Melt 4 tablespoons butter in

Step 3

a large pot over medium heat.

Step 4

Add squash, onion, and garlic.

Step 5

Season with salt and pepper. Cook,

Step 6

stirring occasionally, until just

Step 7

tender, 12 to 15 minutes. Drain and

Step 8

roughly chop mixture; reserve. Add soup and milk to pot and cook until warm, 1 to 2 minutes. Whisk in cheese, 1/2 cup at a time, until melted. Stir in egg and reserved squash mixture. Transfer mixture to prepared

Step 9

baking dish.Melt remaining 2 tablespoons

Step 10

butter. Add crackers and toss

Step 11

to coat. Sprinkle over casserole.

Step 12

Bake until golden and bubbly,

Step 13

35 to 40 minutes. Serve warm.