Bring salmon filets out of the refrigerator 15 minutes prior to cooking.
Season both sides with salt and pepper.
Heat a skillet to medium-high heat.
Add grape seed oil to the pan, then add salmon flesh side down, gently pressing to help the sear.
Cook salmon for 5 minutes on each side.
Remove from pan and set aside.
Add butter to the pan and let it melt. Add garlic and saute for 30 seconds, stirring continuously.
Add onions and sauté until translucent, about 2 minutes.
Deglaze the pan with vegetable stock, scraping with a wooden spoon to get any brown bits from the bottom.
Season with salt and red pepper flakes.
Add cherry tomatoes and cook for 3-4 minutes. Press down on them with a spoon to make them burst.
Add spinach and sauté until wilted, about 2 minutes.
Pour in the coconut milk. Stir and simmer for 3-4 minutes.
Add lemon juice and fresh basil. Stir to combine.