Step 1In a small sauté pan, heat the oil over medium-high heat until hot. Add the garlic and sauté until aromatic, then remove the pan from heat. Stir in the chile arbol. Set aside to cool for 10 minutes, then whisk in the agave syrup and lemon juice. Set aside. This makes more chile water than is needed for the remainder of the recipe; the mixture can be used as a marinade and will keep, covered and refrigerated, up to 1 week.
Step 1In a small bowl, stir together the salt, pepper, cumin and coriander. Pat the spice blend all over the salmon fillet.
Step 2Heat a heavy-bottomed skillet or sauté pan over medium-high heat until hot. Add the oil and sear the salmon quickly on both sides. Remove the salmon and set aside until cool enough to cut. Dice the cooled fillet into cubes one-third to one-half inch thick and refrigerate until chilled.
Step 3In a large bowl, combine the diced salmon with the orange, serrano chiles, red onion, aji amarillo purée, chile water, cilantro and green onions. Taste and season if desired with salt and pepper.