Preparation 10 minutes, cooking 5 to 10 minutes.
Place the fish in a steamer basket (personally, I use a bamboo basket). Cook it for 5-10 minutes depending on the size of the fillet. Be careful not to overcook it.
Prepare the thyme oil by mixing olive oil, fresh thyme and a pinch of fior di sale in a blender.
Pour the thyme oil over the fish, add a little grated lemon zest, lemon salt crystals, ground pepper and fresh thyme.