Sprinkle chicken with 1 tsp taco seasoning and toss to coat. Preheat skillet with oil and add chicken. Cook for 5 minutes or until white edges appear, turn and cook for 5 more minutes or until cooked through. Transfer to a cutting board and shred with 2 forks. Set aside.
Wipe baking dish dry, spread a few tablespoons of tomato sauce mixture and sprinkle with quinoa. Place sliced zucchini overlapping a bit to create a single layer. Top with 1/3 of shredded chicken, then a bit of cheese and 1/3 of tomato sauce. Repeat until you run out of ingredients and sprinkle the top with remaining cheese.