Rinse the quinoa under cold water, then combine with 0.5 cup water in a small saucepan. Bring to a boil, reduce heat to low, cover, and simmer for 15 minutes or until water is absorbed.
Season both sides of the chicken breast with sea salt and black pepper.
Heat the olive oil in a medium skillet over medium-high heat. Once shimmering, add the chicken breast and sear for 6 to 7 minutes per side until the exterior is golden brown and the internal temperature reaches 165°F.
While the chicken cooks, steam the broccoli florets in a steamer basket over boiling water for 4 to 5 minutes until tender-crisp and bright green.
Remove the chicken from the skillet and let it rest on a cutting board for 3 minutes.
In the same skillet used for the chicken, reduce heat to medium and add the minced garlic. Sauté for 30 seconds until fragrant, then stir in the lemon juice and lemon zest to create a light pan sauce.
Slice the chicken into strips. Fluff the quinoa with a fork and plate it alongside the steamed broccoli.
Top the quinoa and chicken with the lemon-garlic pan sauce and garnish with freshly chopped parsley.