1Preheat oven to 375 degrees F.Coat a 2-quart casserole dish coated with cooking spray.
2Place flour in a large saucepan,Gradually add greek yogurt and milk,stirring with a whisk until blended.Cook over medium heat until thick(about 8 minutes),stirring constantly.Add cheeses;cook 3 minutes or until cheese melts,stirring frequently.
Remove from heat;stir in macaroni,olives and greek seasoning.
3Spoon mixture into a prepared casserole dish.
Bake at 375 for 30 minutes or until bubbly.