Melting salmon in fragrant salt, tarator style

Name: Melting salmon in fragrant salt, tarator style
Prep time: 35 min
Cook time: 30 min
Total time: 1 h 5 min
Cuisine: Middle Eastern
Ingredients: 1 side salmon (about 1.4kg), skinless, pin-boned, at room temperature; 80 ml extra-virgin olive oil (⅓ cup); of 1 lemon, Juice; 2 tbsp sea salt flakes; ½ tsp each cumin seeds, coriander seeds, cardamom seeds, fennel seeds and nigella seeds, finely ground; ½ tsp sesame seeds, toasted; 100 gm walnuts; 2 small Spanish onions, very finely diced; 1 cup coriander, shredded (firmly packed); ½ cup mint, shredded (firmly packed); 1 long red chilli, seeds removed, very finely chopped; 3 tsp sumac; 100 gm thick plain yoghurt; 30 gm unhulled tahini; of 1 lemon, Juice; 1 small garlic clove, crushed with ½ tsp sea salt