I adapted a recipe I found on Epicurious for Pan-Seared Tuna with Ginger-Shiitake Cream Sauce. The first obvious change I made was to use mahi mahi; this dish would taste good with the tuna suggested or many other fish, but I just went with what I had on hand.
Regardless of the fish you use, the prep is the same: season it with salt and pepper, then cook in a little olive oil and keep warm in the oven while you make your sauce.
Mahi Mahi with Ginger, Lime & Mushrooms
adapted from Epicurious
1.5 lbs. mahi mahi, tuna steak, swordfish, etc.
2 tablespoons olive oil
3 tablespoons butter or coconut oil
1/3 cup thinly sliced green onions
1/4 cup chopped cilantro
2 tbs. finely chopped peeled fresh ginger
4 minced garlic cloves
8 ounces fresh shiitake mushrooms, stemmed, caps sliced
6 tbs. coconut aminos
juice of one lime
3 tablespoons fresh lime juice
avocado, for topping
Preheat oven to 200°F. Sprinkle 1 side of mahi mahi with salt and pepper. Heat 2 tbs. oil in heavy large skillet over high heat. Place fish, seasoned side down, in hot oil and sear 2 minutes. Turn over, season the flipped side and continue cooking until fish begins to flake with a fork. Transfer to rimmed baking sheet; keep warm in oven.
Add butter, sliced green onions, cilantro, ginger and chopped garlic to same skillet and sauté until fragrant, about 30 seconds. Mix in mushrooms and coconut aminos and simmer 30 seconds.
Add coconut milk and simmer until sauce lightly coats back of spoon, about 3 minutes. Stir in lime juice. Remove fish from oven and plate, pouring mushroom sauce over the top. Garnish with lime wedges and cubed avocado, if desired.