Bring a pot of salted water to a boil and cook the whole wheat penne according to package instructions.
Before draining the pasta, reserve 2 tablespoons of the starchy pasta water for the sauce.
Steam the broccoli florets for 4-5 minutes until they are tender but still vibrant green.
Season the chicken breast with sea salt, black pepper, and onion powder on both sides.
Heat the olive oil in a large skillet over medium-high heat and cook the chicken for 6-7 minutes per side until golden and cooked through.
Remove the chicken from the pan, let it rest for a few minutes, then slice it into thin strips.
In the same skillet, reduce the heat to medium and sauté the minced garlic for about 30 seconds until fragrant.
Whisk in the Greek yogurt, parmesan cheese, and reserved pasta water, stirring constantly until the sauce is smooth and warm.
Add the cooked pasta, steamed broccoli, and sliced chicken back into the skillet.
Toss everything together gently until the pasta is thoroughly coated in the garlic parmesan sauce and serve immediately.