Whisk all ingredients together in a medium bowl, season with salt and pepper to taste.
Salmon:
Preheat oven to 400 degrees F. Rub each fillet with olive oil, season to taste with salt and pepper, and wrap envelope style in a banana leaf rectangle. Place seam-side down on a sheet pan and roast 8 to 10 minutes. When done, the fish will look a bit undercooked on top but will be firm and opaque. Place the packets seam-side up on a platter and fold back the sides of the banana leaf.
Roasted Vegetable Couscous:
Preheat oven to 400 degrees F. Place the vegetables in a medium baking dish, toss with the olive oil and season with salt and pepper. Roast for 8 to 10 minutes until vegetables are just cooked through. Bring vegetable stock, saffron and 1 teaspoon of salt to a boil in a medium saucepan, let boil for 5 minutes, until saffron blooms and colors the stock. Add the couscous, stir, cover and reduce heat to low. Cook until all liquid is absorbed, 8 to 10 minutes. Place couscous in a large bowl, add the roasted vegetables and parsley and season with salt and pepper to taste. Serve with salmon and ancho chile-ginger sauce. Garnish with diced red pepper and cilantro.