Step 1

To a large, heavy-bottomed skillet (such as cast iron), add half the olive oil, salmon (skin side down if it has skin), and sear over medium heat for about 4 minutes (no skin) and 6 minutes (with skin) or until the salmon forms a nice little crust.

Step 2

Flip it and cook for another 3 to 4 minutes, or until cooked through and as done as desired; remove it from the skillet and set aside on a plate. Tip - Do not overcook it. The salmon will also continue to cook from the internal heat and carryover cooking even after you remove it from the skillet so take this into account.

Step 3

Add the remaining oil, mushrooms, and cook for about 4 minutes or until they're beginning to soften; stir frequently.

Step 4

Add the garlic and cook for 1 minute or until fragrant; stir nearly constantly.

Step 5

Add the heavy cream, wine, lemon juice, Parmesan, and simmer for 3 minutes; stir intermittently.

Step 6

Optionally add the butter and allow it to melt (recommended because it adds great richness) and add the salt and pepper to taste, and stir to combine.

Step 7

Add the spinach, turn the heat to low, cover the skillet with a lid, and allow the spinach to wilt, about 3 minutes.

Step 8

Optionally sprinkle with red pepper flakes and serve immediately. Salmon is best warm and fresh but extra will keep airtight in the fridge for up to 3 days or in the freezer for up to 3 months; reheat gently and slowly to avoid breaking the cream sauce.