Bring a large pot of salted water to a boil and cook the whole wheat penne according to package directions until al dente.
Reserve 0.25 cup of the hot pasta water before draining the noodles.
Season the chicken breast on both sides with sea salt and black pepper.
Heat olive oil in a large skillet over medium-high heat and sear the chicken until golden and cooked through, then set aside to rest.
In the same skillet, reduce heat to medium and sauté the minced garlic for 30 seconds until fragrant.
Add the fresh spinach to the skillet and cook until just wilted.
In a small bowl, whisk together the Greek yogurt and grated parmesan cheese until smooth.
Slice the rested chicken into thin strips.
Add the cooked pasta, yogurt mixture, and reserved pasta water to the skillet, tossing gently until the sauce is creamy and coats the noodles.
Stir in the sliced chicken and garnish with fresh parsley before serving.