Slice the chicken breasts into strips, about 1/2-inch thick. Season them with salt, pepper, paprika, oregano, garlic powder, and cumin. Toss to coat the chicken evenly with the seasoning.

Heat 1 tablespoon of olive oil in a large skillet over medium-high heat. Add the seasoned chicken strips in a single layer and cook for 5-7 minutes until the chicken is browned and cooked through.

Ensure the chicken reaches an internal temperature of 165°F (74°C). Once cooked, remove the chicken from the skillet and set aside.

In the same skillet, add the sliced onion and minced garlic. Sauté for 2-3 minutes until fragrant and softened.

Add the bell peppers, zucchini, broccoli, carrots, and cherry tomatoes. Stir well and cook for another 7-10 minutes, stirring occasionally, until the vegetables are tender but still vibrant. The vegetables should maintain a slight crunch.

Once the vegetables are nearly cooked, add the chicken broth to the skillet. Stir to scrape up any browned bits from the bottom of the pan, infusing those flavors back into the dish.

Return the cooked chicken to the skillet with the vegetables. Stir in the lemon juice, balsamic vinegar (if using), and Dijon mustard (if using).

Let everything cook together for 2-3 more minutes to ensure the flavors meld together.

Once everything is heated through and coated in the sauce, remove the skillet from heat. Sprinkle with fresh parsley and, if desired, a pinch of crushed red pepper flakes for a bit of heat.

Optionally, sprinkle a bit of freshly grated Parmesan cheese on top for a creamy, savory finish.