Fine dice the onion, tomatoes and mushrooms.
Heat olive oil, add the onion, steer until transparent.
Add the diced mushrooms, steer until they are moistury.
Add the tomato paste and let it bake for a while until it’s runny.
Add the cream, cut the salmon into bite ready pieces and add it as well.
Season with oregano, pepper, a pinch of salt (be careful with the salt as the salmon and shrimps both give it a salty flavour too)
Keep steering occasionally, add the diced tomatoes, and keep below boiling point.
Before serving, add half the shrimps to the mass. Serve with tagliatelle or other pasta of choice. As a presentational bonus you can add some spring onion green, extra fine diced tomatoes, and some of the remaining shrimps on top of the plate.