If using fresh or frozen squash, cook it until fork-tender. Miss Joan microwaved hers with a bit of water, but stovetop works too. Drain completely and mash or pulse in a food processor to soften the texture.

In a small skillet, melt butter and sauté the chopped onion and bell pepper until soft and fragrant.

In a large bowl, combine the mashed squash, sautéed veggies, eggs, mayonnaise, and shredded cheddar cheese. Stir until well mixed. Add salt and pepper to taste.

Preheat the oven to 350°F (175°C). Spray a casserole dish with cooking spray and pour in the squash mixture, spreading evenly.

In a zip bag, crush the crackers. Mix them with melted butter, then sprinkle evenly over the casserole. Drizzle a little extra butter in a zigzag motion over the top for extra golden crispness.

Bake uncovered at 350°F for 30–40 minutes, or until golden brown and bubbling around the edges.