Heat oil in a large pot or Dutch oven, over medium heat. Add red onion and sauté for 3 minutes. Add the ginger, and garlic and sauté, stirring occasionally until softened, about 20 to 30 seconds. Add miso, salt, and black pepper. Cook until miso is slightly caramelized, about 2 minutes.
Add coconut milk and ½ cup water and bring to a boil over high heat. Cover and cook until liquid is slightly reduced, about 5 minutes. Stir in the salmon, reduce the heat to medium-low and simmer gently about 8-10 minutes depending on the thickness of the salmon. Remove from the heat and stir in spinach and lime juice.
Divide rice among bowls. Top with salmon curry, basil, and cilantro. Serve with lime wedges for squeezing on top. Enjoy!
