Cut the mushrooms in half lengthwise.

Heat olive oil in a frying pan over medium heat, add the salted salmon, and cook for about 5 minutes until both sides are browned. Remove, then debone and flake the salmon coarsely.

In the same pan, add the mushrooms and sauté over medium heat. Add the canned tomatoes and cook to evaporate excess moisture. Then, add water, salt, and garlic paste.

Once the mixture boils, break the spaghetti in half and add it to the pan. Stir, add the flaked salmon, cover, and cook according to the spaghetti's package instructions.