Cut of the woody ends of the asparagus.
Heat the oil or 1 knob of butter in a large, shallow pan together with the capers and garlic.
When the butter has melted and the garlic is starts browning add the asparagus and rotate in the oil. Turn the heat down and put the lid on. Cook for 1 minute.
Place the haddock on top the asparagus, scatter the lemon zest all over, then squeeze the lemon juice on top.
Season with salt and pepper, then put a small crumble of butter on top of the fish fillets or drizzle with a drop of oil. Scatter the dill all over.
Put the lid on and sauté for about 5-8 minutes, depending on the thickness of the fish.
Serve immediately.