Southwestern Chicken, Squash, and Cornbread Casserole

Preheat the oven to 375 degrees F (190 degrees C). Grease a 7x11-inch baking dish.

Heat olive oil in a large skillet over medium heat. Add zucchini and yellow squash; cook, stirring frequently, until fork-tender, about 4 minutes. Stir in white and light green parts of scallions, chili powder, cumin, and garlic powder. Set aside scallion tops for garnish.

Add drained corn, drained tomatoes, and chicken. Cook, stirring occasionally, until most of the liquid in the skillet has evaporated, about 5 minutes. Season with salt and pepper. Pour the contents of the skillet into a large mixing bowl.

Pour evaporated milk into the same skillet. Toss Cheddar cheese with cornstarch and add to the skillet; stir frequently until cheese is melted and blended, about 2 minutes. Stir in cilantro.

Pour the cheese sauce over the vegetables and stir to combine. Taste and adjust seasonings.

Combine cornbread mix, milk, and egg in a large bowl. Stir until smooth. Carefully pour over the casserole; the dish will be full. Dot with jalapeno slices.

Bake in the preheated oven until cornbread is set and browned, 25 to 30 minutes. Allow to cool slightly. Garnish with scallion tops.