Mix all the sauce ingredients in a bowl and brush the sauce over the salmon fillets. Trim 3-4 cm from the woody part at the bottom of the asparagus spears. Season with salt and pepper.
Cover the salmon fillets and asparagus with baking parchment and then aluminium foil on top.
Bake in a preheated oven for 10 minutes at 210°C, then remove the foil and the paper and bake for another 2-3 minutes.