Heat a 12-inch (30.5cm) skillet over medium heat, and add 2 tablespoons of the oil. When the oil is hot, add the corn and sauté for 2 minutes.
Add the onions, and sauté for 2 minutes.
Add the calabaza and tomatoes, and sauté for 2 minutes. Transfer the cooked vegetables to a bowl.
Add the remaining 2 tablespoons of oil to the pan, and increase the heat to medium-high. Add the chicken, and sauté for 4 or 5 minutes. The chicken will begin to turn a golden-brown color and leave a little fond (the caramelized bits) on the bottom of the pan.
Add the cumin, garlic, and pepper, and sauté, stirring constantly to incorporate, for 1 minute.
Return the cooked vegetables to the pan, add the tomato sauce, and pour in the chicken broth. It should slightly cover all the ingredients in the pan. Bring to a simmer, stirring to scrape the fond off the bottom of the pan. Reduce the heat to medium, cover, and simmer for 15 minutes. If it’s boiling too fast, reduce the heat a bit more.
Serve in a bowl with warm corn tortillas. No other sides needed; this is a complete, filling, and delicious meal in one bowl.
