01 - 
                Set the oven temperature to 232°C (450°F) and allow it to preheat fully.
              
              
              
                02 - 
                Cut 4 pieces of aluminium foil, each measuring 30 cm in length. Distribute one quarter of the asparagus and sliced onion onto each piece of foil.
              
              
              
                03 - 
                Place a salmon fillet atop each bed of vegetables. Drizzle 1 tablespoon olive oil over each, and season generously with salt and black pepper.
              
              
              
                04 - 
                Add approximately three lemon slices over each salmon fillet and top with a fresh dill sprig.
              
              
              
                05 - 
                Bring the long sides of the foil together over the salmon and fold to seal. Fold in the short ends tightly. Arrange packets seam-side up on a baking tray and place in the oven.
              
              
              
                06 - 
                Bake for 15 to 18 minutes until the salmon is just opaque and flakes easily with a fork.
              
              
              
                07 - 
                Carefully open the foil packets to avoid steam. Serve immediately, optionally with cooked rice.