Prepare the asparagus by chopping off the bottom woody part of the asparagus which you don’t want to eat. Heat 1 tbsp of butter in your pan and add in the garlic. Once the butter has melted and the garlic is tarting to brown add in the asparagus and season with salt and pepper. Add in about 50ml of water and cover and cook with the lid on for about 4-5 minutes.
After 4-5 minutes the water will evaporate and you want to cook the asparagus till it’s perfectly tender and has some colour on it. Once you have achieved that remove the asparagus and set it aside.
In the same pan add a tbsp of butter and while it melts season your salmon filet with salt and pepper and then place in the frying pan. Cook for about 3-4 minutes each side till it’s perfectly cooked all the way through or to your liking. Remove and set the fish aside.
Then add 1 tbsp of butter to the pan along with the red onion and fry. Add in the lemon zest, lemon juice, capers and 2 tbsp of water. Mix well and let it cook for a minute. Then add in the heavy cream and if it’s too thick add some more water.
Taste and season as required and finish the sauce with some fresh parsley. Serve the fish over a bed of asparagus and pour the sauce right over it.