Heat a large cast-iron skillet over medium-high heat.
Add the lean ground beef and cook for about 5 minutes, breaking it apart with a spoon until browned and cooked through.
Stir in the chopped onion, minced garlic, and taco seasoning.
Cook for 1–2 minutes until the onion softens and becomes fragrant.
Add the chopped tomato and stir well.
Reduce heat to medium-low and continue cooking for 7–10 minutes, allowing excess liquid to reduce and flavors to develop.
Add the chopped bell peppers and zucchini.
Stir everything together and cook for about 2 minutes. The vegetables should remain slightly crisp for the best texture.
Remove from heat and garnish with fresh cilantro.
Serve immediately with your favorite toppings.
This Healthy Ground Beef Vegetable Skillet Recipe tastes wonderful on its own or served over rice, cauliflower rice, or quinoa.