Preheat oven to 400°F and line a baking sheet with parchment paper.
Slice the zucchini into half-moons and place on the tray with cherry tomatoes, drizzling with olive oil and a pinch of salt.
Roast the vegetables for 15-20 minutes until the tomatoes are blistered and the zucchini is tender.
Meanwhile, boil the whole wheat penne in salted water according to package directions, reserving 2 tablespoons of pasta water before draining.
Season the chicken breast with oregano, salt, and pepper, then sauté in a non-stick pan over medium heat until golden and cooked through.
In a small bowl, whisk together the Greek yogurt, minced garlic, and parmesan cheese to create the base for the sauce.
Slice the cooked chicken into strips and return to the pan over low heat.
Add the cooked pasta, roasted vegetables, spinach, yogurt mixture, and reserved pasta water to the pan.
Toss everything gently until the spinach is wilted and the sauce is creamy and well-distributed.