Preheat your oven to 400°F and line a baking sheet with parchment paper.
Slice the zucchini into half-moons and toss them on the baking sheet with 0.5 tbsp of olive oil, 0.125 tsp of sea salt, and 0.125 tsp of black pepper.
Roast the zucchini for 15 to 20 minutes until they are tender and show light golden edges.
While the zucchini roasts, season the chicken breast evenly with the dried oregano, lemon zest, and the remaining salt and pepper.
Heat the remaining 0.5 tbsp of olive oil in a medium skillet over medium-high heat.
Place the chicken in the skillet and sear for 6 to 7 minutes per side, or until the internal temperature reaches 165°F.
In the final minute of cooking, add the minced garlic and lemon juice to the pan, swirling to combine and spooning the pan sauce over the chicken.
Plate the chicken alongside the roasted zucchini and the warm cooked quinoa, drizzling any remaining pan juices over the top.