Heat the olive oil in a large nonstick skillet over medium-high heat. Add the onion and cook for 2 minutes, until it starts to softened. Add the ground chicken and minced garlic and cook until the meat is almost cooked through, breaking it into crumbles with a spoon as it cooks.

Add the salt, pepper, quinoa, chicken broth and 2 tablespoons of the lemon juice, stirring until everything is combined. Cover the skillet with a lid, lower heat to medium-low and simmer for 20 to 25 minutes, or until the quinoa is cooked.

Stir in the remaining lemon juice, lemon zest and spinach. Stir until spinach is wilted. Sprinkle the shredded cheese on top, cover with the lid and cook until the cheese is melted.