Step 1Skin the salmon and remove any pin bones. Season it lightly with salt and pepper and place the filet skin side down on a baking sheet lined with foil or parchment. Leave it at room temperature while heating the oven to 300 degrees.
Step 2Rinse the preserved lemon wedges and finely chop them. Combine the lemons with the parsley, cilantro and olive oil and season to taste with pepper.
Step 3Bake the salmon without turning until the juices begin to seep out around the edges, 18 to 20 minutes.
Step 4When the salmon is nearly done, toast the pappadums directly over a gas flame or electric burner on very low heat, turning frequently, until puffed up and crisp, 1 to 2 minutes.
Step 5To serve, divide the salmon among 4 dinner plates and spoon the lemon relish alongside. Break the pappadums into 3 or 4 pieces each and lean them against the salmon.
Step 1Wash and dry the lemons. Set aside 10 for juicing; cut the rest into 6 wedges if small, 8 for average-size lemons.
Step 2Sprinkle a little salt into a large clean glass jar. Add a layer of lemon wedges, sprinkle them generously with salt, and continue adding lemons and salt, pressing down with a spoon to eliminate air pockets. Some juice will soak out of the lemons right away; top with lemon juice to barely cover the lemon wedges, then cover the jar and let stand at room temperature for a week, turning the jar daily to redistribute the salt and juice. Pour in a half-inch layer of olive oil and store in a cool pantry or in the refrigerator for up to 4 months.