Place one tablespoon of the olive oil in a heated frypan and when hot, add in the ocean trout, skin-side down. Hold each portion down for 30 seconds using a pallet knife to keep flat. Cook for several minutes until the skin becomes golden and crisp. Turn and cook the other side, keeping the centre moist and glossy. Remove and set aside.
Add one tablespoon of olive oil to a heated saucepan and add in the garlic. Cook for 20 seconds, and then add in the onions and fennel seeds. Cook for several minutes then combine in the vongole and sherry. Bring to a boil, place the lid on and cook for several minutes until all the vongole have opened.
Remove from the heat, add in the diced tomatoes and parsley then season well.
Present with the crispy skin ocean trout and finish with a scattering of the cress.