Bring a pot of salted water to a boil and cook the whole grain penne according to package directions.
Add the broccoli florets to the pasta water during the last 3 minutes of cooking, then drain and reserve 2 tablespoons of pasta water.
While pasta cooks, heat olive oil in a large skillet over medium-high heat and add the diced chicken breast.
Season the chicken with sea salt and black pepper, cooking until golden brown and cooked through.
Reduce heat to low, add minced garlic to the skillet, and sauté for 1 minute until fragrant.
In a small bowl, whisk together the Greek yogurt, grated parmesan cheese, and the reserved pasta water.
Add the cooked pasta and broccoli to the skillet with the chicken.
Pour the yogurt mixture over the pasta and toss gently over low heat until the sauce is velvety and coats everything evenly.
Garnish with fresh chopped parsley and serve immediately.