Preheat your oven to 425°F.
In a small bowl, combine the lemon juice, olive oil, and a generous pinch of your favorite herbs (such as thyme and parsley) to create a vibrant marinade.
Place the chicken breast on a cutting board and gently pound it to an even thickness. Brush both sides with the lemon herb marinade and let it sit for about 10 minutes.
Meanwhile, chop the zucchini, red bell pepper, and broccoli into bite-sized pieces. Toss them lightly with a drizzle of olive oil, salt, and pepper.
Arrange the marinated chicken on a baking sheet lined with parchment paper. Spread the mixed veggies around the chicken.
Roast in the oven for approximately 18-20 minutes until the chicken is cooked through and the vegetables are tender and slightly caramelized.
While roasting, prepare the quinoa as per package instructions if not pre-cooked.
Slice the roasted chicken and serve it over a bed of quinoa, topped with the roasted vegetables. Enjoy your warm, fresh, and nutrient-packed bowl!