Preheat oven to 400F/200C.
Cut the base off the fennel bulb, cut in half lengthwise and remove the core. cut into slices and cut any larger slices into smaller pieces. Put in an oven dish and toss with some olive oil and a little salt.
Put the fennel in the oven to cook while you prepare the rest (it should have around 5-10 minutes longer).
Start the lentils cooking according to packet instructions - generally bring to boil in around 2 cups/480ml water, reduce to simmer and cook around 10min, until tender.
Lay the swordfish and asparagus (with ends trimmed) on a baking sheet/tray. Drizzle over some olive oil and turn both the fish and asparagus so coated on all sides. Sprinkle over a little salt and pepper.
Place the tray in the oven and cook 10-15 minutes until the swordfish is cooked through but not overcooked (the timing depends how thick the pieces are and on your oven).
Remove the fennel from oven when it is starting to brown and tip into the lentils, including any residual olive oil. Serve alongside the swordfish and fennel, with chermoula drizzled over the fish and lentils.
Note - if you prefer, you can grill the swordfish and asparagus, then simply saute the fennel until tender and mix it through the lentils.