Preheat your oven to 190 degrees.
To make the dressing, place the grated zest of one lemon and the juice from the same lemon into a small bowl or jar. Next, add the seeded mustard, salt, and pepper to the bowl, and mix to combine into a dressing.
Line your baking tray with foil, followed by baking paper, and place your salmon fillets on top.
Snap off the wooden ends of your asparagus and place to the side, along with the cherry tomatoes, cut in half.
Pour the dressing over the top of the four salmon fillets evenly. Fold the baking paper over the fillets, followed by the foil. Ensure the ends of the foil are wrapped up nice and tight.
Bake in the oven for 20-25 minutes, until cooked through.
Whilst the salmon is baking, place your asparagus in a pan and drizzle with the coconut oil.
When the asparagus is almost cooked, throw in the tomatoes for a few minutes until they are soft.
Plate up the salmon, asparagus and tomatoes. Serve with rocket and lemon to taste.