Run frozen Alaska halibut fillets under cold water to remove any ice glaze and pat dry with a paper towel.
Sauté the aromatics
Heat the coconut oil in a large sauté pan over medium heat. Add the onion, garlic, and ginger, and cook until everything is aromatic and the onions are translucent, about 2 minutes.
Combine sauce and cook halibut
Pour in the coconut milk, soy sauce, salt, and vinegar, and stir to combine. Bring to a gentle boil, add the halibut, and reduce the heat to a very gentle simmer. Cover and cook until halibut is just cooked through and opaque, about 10-12 minutes depending on thickness and doneness. Halibut should be opaque and flake easily with a fork. Carefully transfer halibut to a plate.
Cook optional greens
With the heat still on, throw in spinach or other leafy greens into the poaching liquid. Using tongs, mix until just wilted (about 2 minutes), then remove.
Make the salsa
While the halibut is poaching, mix together the mango, avocado, cilantro, and lime juice in a bowl. Season with salt to taste. If you like a little heat you can add a pinch of cayenne as well.
Plate and serve
Serve poached halibut over steamed jasmine rice. Spoon some of the poaching liquid on top, then top with mango-avocado salsa.
Poaching wild alaskan halibut is a quick and easy way to prepare halibut!