1. Preheat oven to 350.
2. Prepare rice mix according to directions, set aside.
3. Melt butter in large skillet over medium heat, add onions and celery. Saute 10 minutes.
4. Stir in rice, chicken, 1 1/2 cups cheese, soup and next 4 ingredients.
5. Spoon mixture into lightly greased 11x7 dish or 2 quart casserole dish.
6. Top casserole evenly with breadcrumbs/panko crumbs.
7. Bake at 350 for 25 minutes. Sprinkle with remaining cheese and bake for 5 minutes.