Heat the avocado oil in a large skillet over medium-high heat.
Add the diced sweet potato and cook for 4 to 5 minutes, stirring occasionally.
Add the zucchini, bell pepper, red onion, and garlic. Cook for another 3 to 4 minutes, until the vegetables begin to soften.
Push the vegetables to one side of the skillet and add the ground beef to the other side. Cook for 7 to 9 minutes, breaking it into small crumbles as it browns. Drain excess grease if needed.
Reduce the heat to medium-low. Add the black beans, fire-roasted tomatoes with their juice, frozen corn, and taco seasoning.
Stir everything together well so the flavors combine evenly. This Ground Beef and Zucchini Skillet should look rich, colorful, and well mixed.
Sprinkle the shredded cheese over the top, cover the skillet, and remove it from the heat. Let it sit for about 2 minutes, or until the cheese is melted.
Remove the lid, add cilantro and green onions if desired, and serve warm.