Heat oven to 200C/180C fan/gas 6. Blitz the 2 whole garlic cloves with most of the parsley, the lemon zest, bread and some seasoning. Season the salmon fillets, then press the crumb mixture on top. Drizzle with 1/2 tbsp oil and bake in the oven for 15-20 mins until the fish is cooked through and the crumbs are golden.
Cook the sliced garlic in the remaining oil in a frying pan for 1-2 mins over a low heat. Add the spinach and lentils, turn up the heat and cook until the spinach has wilted and the lentils are hot through. Stir in the crème fraîche, horseradish and seasoning.
Divide the lentils between 4 plates. Place the fish on top, sprinkle with the remaining parsley and serve with lemon wedges.