In a skillet, melt 2 tablespoons of butter over medium-high heat. Add the chopped zucchini and 1 teaspoon of onion powder, stirring frequently. Cook for about 10-12 minutes until tender and slightly golden.

Transfer the cooked zucchini to a large bowl and allow it to cool slightly for about 5 minutes.

In a microwave-safe bowl, melt the remaining 2 tablespoons of butter and stir in the crushed Rice Chex until well coated.

To the cooled zucchini, add 1.5 cups of shredded cheese, 2 beaten eggs, and salt and pepper to taste. Mix until fully combined.

Preheat your oven to 350°F. Grease an 8-inch square baking dish. Pour the zucchini mixture into the dish and spread evenly.

Top with the Rice Chex mixture and ensure an even layer covers the casserole.

Bake for 25-30 minutes until the top is golden brown and the casserole is set.

Allow the casserole to cool for about 10 minutes before serving.