Start by placing the salmon skin into a large skillet over medium heat filled with hot vegetable oil, fry it until golden brown then set it aside.
Next, make shallow cuts in the skinless salmon fillet - first, cut diagonally then cut diagonally in the opposite direction.
Add the unsalted butter softened to room temperature over everything and spread it.
Season with the salt, the black pepper, the garlic powder and cut it into strips.
In a large skillet over medium to low heat, add a drizzle of olive oil.
Add the salmon strips and fry them until both sides are golden brown.
Remove from the skillet and set aside.
In a large skillet over medium to low heat, add a drizzle of olive oil, the onion cut into strips, the crushed garlic cloves and sauté until lightly golden brown.
Add the mushrooms cut into smaller pieces, the cherry tomatoes cut in half, the spinach leaves, the grated Parmesan cheese and the heavy cream.
Season with the salt, the black pepper and sauté for 5 minutes.
After this time has passed, add the salmon we prepared and the lemon sliced into rounds.
Cover the skillet and let everything simmer for 10 minutes.
To finish, add the salmon skin that we fried earlier.
Serve.