Flake salmon into a medium bowl. Add onion and celery; stir until well combined.
Stir in flour, salt and pepper. Fold in yogurt and eggs. (Add another 1 tablespoon of flour if mixture is very wet.)
Use a dry ⅓-cup measure to make 8 portions; shape into ½-inch- thick patties.
Place patties on a tray, cover and refrigerate until firm, at least 1 hour or up to overnight.
Place a large rimmed baking sheet in oven; preheat to 400ºF.
When hot, remove baking sheet from oven and mist with cooking spray.
Carefully place patties on baking sheet, spacing them apart, and mist tops of patties with cooking spray.
Bake until bottoms of patties are golden, about 10 to 15 minutes.
Carefully flip and continue baking until golden all over and heated through, about 10 to 15 minutes longer.
Serve hot, or let cool, cover and refrigerate to serve later.
