Pulled Chicken and Summer Squash Casserole

Preparation

1. Preheat the oven to 400F. Lightly grease a baking tray and a 9x10-inch baking dish.
2. Slice squashes into 1/2-inch pieces and distribute in a single layer on the baking tray. Add the chopped pepper and roast until the squash appears about half done, 15 to 20 minutes. Remove the vegetables from the oven and set aside.
3. Reduce the heat to 350F.
4. While the squash roasts, slice the chicken breasts lengthwise. Place the chicken in the bottom of a medium saucepan or Dutch oven. Add just enough water to cover the chicken and season the water with 1/4 teaspoon of salt. Bring the pot to a simmer over medium heat; do not allow it to boil. Reduce the heat to low and simmer, covered, until the thickest part of the chicken breasts cook through, about 20 minutes. Remove the chicken to a plate and allow it to cool. Pour 1/2 cup of the broth into a heatproof measuring cup; reserve the rest for another use or discard.

1. While the chicken cools, in the same saucepan, whisk together the milk, cornstarch, ground chile, 3/4 teaspoon salt, and black pepper. Stir in the 1/2 cup of warm chicken broth and stir the mixture over medium heat until it thickens and begins to bubble, about 5 minutes.
2. Remove the white sauce from the heat. Spoon 1/2 cup sauce into the baking dish and top with 3 corn tortillas, tearing the tortillas as needed to arrange them in a single layer.
3. Use two forks to shred the chicken, then stir it into the sauce along with the cooked squash and peppers, 1½ cups of cheese, and chile flakes if using. Spread half of the mixture in the baking dish, top with three corn tortillas, then with the other half of the chicken mixture. Top with halved cherry tomatoes and sprinkle with the remaining 1/2 cup of cheese.
4. Bake until the sauce bubbles and the casserole is golden brown on top, about 30 minutes. Serve promptly.

Ingredient Variations and Substitutions

The meat from one pre-cooked rotisserie chicken can be substituted for the chicken in this recipe. The chicken meat can be cubed with a knife instead of shredded, if preferred.

To make the recipe gluten-free, use gluten-free tortillas.

Zucchini can be substituted for some or all of the summer squash.

Cooking and Serving Tips

Poaching the chicken over very low heat, as described, is the key to keeping it tender and moist. Boiling will toughen it.

This entree can be assembled ahead of time, refrigerated, and baked for about 40 minutes just before mealtime.