Bring a pot of salted water to a boil and cook the whole grain penne according to package directions until al dente.
While the pasta cooks, cut the chicken breast into bite-sized pieces and trim the asparagus into 1-inch segments.
Heat the olive oil in a large skillet over medium-high heat. Add the chicken and sauté until golden and cooked through.
Add the asparagus and minced garlic to the skillet, sautéing for 3-4 minutes until the asparagus is tender-crisp.
In a small bowl, whisk together the Greek yogurt, lemon juice, lemon zest, sea salt, and black pepper to create the sauce.
Drain the pasta, reserving two tablespoons of the pasta water.
Reduce the skillet heat to low. Add the cooked pasta and the yogurt sauce to the skillet, tossing gently to coat.
If the sauce is too thick, add the reserved pasta water one tablespoon at a time until the desired creamy consistency is reached.
Serve immediately while warm.