Preheat your oven to 375°F (190°C).
Boil the whole wheat penne pasta in salted water until al dente, then drain and set aside.
Dice the chicken breast into bite-sized pieces and season them evenly with sea salt, black pepper, and dried oregano.
Heat the extra virgin olive oil in a skillet over medium heat and sauté the minced garlic clove until fragrant, about 1 minute.
Add the seasoned chicken to the skillet and sear for 3-4 minutes until the edges are browned but the center is slightly undercooked.
In a small mixing bowl, whisk together the low-sodium chicken broth, fresh lemon juice, and lemon zest.
In a small oven-safe baking dish, combine the cooked penne, seared chicken, and fresh baby spinach.
Pour the lemon-broth mixture over the pasta and chicken, tossing well to ensure the spinach begins to wilt and everything is coated.
Sprinkle the grated parmesan cheese evenly over the top of the mixture.
Bake for 15-20 minutes until the chicken is fully cooked through and the cheese has formed a golden, bubbly crust.