Dice the chicken breast into uniform 1-inch pieces to ensure even cooking.
Chop the bell peppers, zucchini, and red onion into bite-sized pieces.
Heat the avocado oil in a large skillet over medium-high heat until shimmering.
Add the chicken pieces to the skillet and season immediately with the ground cumin, garlic powder, sea salt, and black pepper.
Sauté the chicken for 5-6 minutes, stirring occasionally, until golden brown and cooked through, then remove the chicken from the pan and set aside.
In the same skillet, add the onions, peppers, and zucchini, using the remaining oil and juices to coat the vegetables.
Sauté the vegetables for 4-5 minutes until they are tender yet still hold a slight crunch.
Return the cooked chicken to the skillet and toss everything together for 1 minute to combine the flavors.
Remove from heat, drizzle with fresh lime juice, and serve immediately.