Preheat oven to 395 degrees F.

Arrange potatoes in a well buttered 2-quart casserole dish.

Combine the sour cream, chicken stock, onion, butter, flour, salt and pepper.

Pour the mixture over the potatoes.

Cover with foil.

Bake for 45 minutes or until the potatoes are fork tender.

Combine the panko breadcrumbs with the tablespoon of melted butter.

Sprinkle over the potatoes and place back in the oven uncovered until golden brown.

Total cooking time is about 55 minutes.