Boil potatoes until tender.

Peel potatoes and slice thin.

Fry bacon until crisp.

Drain bacon on paper towel and crumble.

Chop onion.

Saute onions in bacon fat until golden brown.

In a separate bowl, blend together flour, sugar, salt, pepper, and celery seed.

Add the flour mixture to the onions.

Cook over low heat, stirring until smooth.

Stir in water and vinegar.

Heat to boil, stirring constantly.

Boil for 1 minute.

Pour the dressing over sliced potatoes.

Crumble bacon on top.

Serve warm.