1. Prepare pasta according to package directions. Drain & set aside.
2. Lightly coat a large stockpot with cooking spray & heat over medium-high. Add chicken & garlic powder. Cook 3-5 minutes or until browned.
3. Add broth, Italian seasoning & cheese. Cook 1-2 minutes or until mixture begins to thicken. Add spinach & tomatoes. Reduce heat & simmer until spinach starts to wilt.
4. Stir pasta into pot. Remove from heat & stir in yogurt. Serve immediately.