In a saucepan over medium heat, soften the onion in 1 tbsp of the butter. Add the celery root and continue cooking for 1 minute. Add the milk and water and bring to a boil. Cover and simmer for 20 minutes or until the celery root is tender. Drain.
In a food processor, purée the celery root with the garlic and the remaining butter. Season with salt and pepper. Keep warm.
Meanwhile, in a large skillet over medium heat, soften the onion in the butter. Add the brown sugar and apple and continue cooking for 5 minutes or until the brown sugar starts to caramelize. Deglaze with the cider vinegar. Add the ice cider and continue cooking for 1 minute. Add the broth and pepper and bring to a boil. Simmer for 10 minutes or until the sauce reduces by half. Season with salt and pepper.
In a non-stick skillet over medium heat, sear the salmon in the butter, flesh side down, for 4 minutes. Season with salt and pepper. Turn the salmon onto the skin side and continue cooking for 4 minutes or until the desired doneness.
Spoon the purée onto plates. Top with the salmon steaks and drizzle with the sauce. Sprinkle with the parsley.
Recipes with the "Healthy Pick" stamp have been evaluated by a registered dietitian member of the Ordre professionnel des diététistes du Québec.