In a bowl, whisk together the olive oil, light brown sugar, fish sauce, soy sauce, grated ginger, lime zest, lime juice, white pepper, and water. This mixture will serve as both a marinade and cooking sauce for the salmon.
Place the salmon fillets in a shallow dish or a resealable bag and pour the marinade over the fish. Ensure each piece is well coated. Allow the salmon to marinate for at least 15 minutes for enhanced flavor.
Using the sauté function on your Instant Pot, add a bit of olive oil and sauté the finely sliced garlic until fragrant, about 1 minute. If using, add the sliced red chili for a bit of heat.
Carefully place the marinated salmon fillets into the Instant Pot on top of the sautéed garlic. Pour any remaining marinade over the fish.
Close the lid of the Instant Pot, ensuring the vent is set to sealing. Set to pressure cook on high for 3-4 minutes, depending on the thickness of your fillets.
Once the cooking time is up, perform a quick release by carefully turning the vent to venting. This will release the steam. Open the lid once the pressure is fully released.
Using a spatula, carefully remove the salmon fillets from the pot. Drizzle the cooked marinade over the top. Garnish with chopped spring onions, fresh coriander, and extra lime wedges for serving.
