Place the bag in the preheated water bath and cook for 30 minutes to 1 hour. Make sure the bag stays submerged for the entire cook. Sous vide magnets can be helpful or place a ceramic plate or bowl on top of the salmon.
To broil: Preheat your oven's broiler on high. Line a rimmed baking sheet with foil and place the sous vided salmon on the sheet. If using pesto or a glaze, spread over the salmon, otherwise drizzle with olive oil or top with pats of butter. Broil for 1-2 minutes, until just browned.
To sear: Preheat a cast iron skillet over high heat. Once hot, add 1 tbsp ghee or other fat of your choice. Place the salmon flesh side down in the hot skillet and sear until just browned. You'll know it's done when it easily releases from the pan with a spatula.