Bring a medium pot of salted water to a boil and cook the whole wheat penne according to package directions until al dente.
While the pasta cooks, season the chicken breast with sea salt and black pepper.
Heat the olive oil in a non-stick skillet over medium-high heat and sear the chicken for 5-6 minutes per side until cooked through and golden brown.
Remove the chicken from the pan, let it rest for 2 minutes, then slice into thin strips.
In the same skillet, reduce heat to low and add minced garlic, sautéing for 30 seconds until fragrant.
Stir in the fresh baby spinach and cook until just wilted.
In a small bowl, whisk together the Greek yogurt, lemon juice, and lemon zest to create the creamy base.
Drain the pasta, reserving 2 tablespoons of the starchy pasta water.
Add the cooked pasta, sliced chicken, and yogurt mixture to the skillet, tossing gently with the reserved pasta water to coat every noodle.
Garnish with freshly chopped parsley and serve immediately.