You may want to roast the brussels sprout veggie mixture for ten minutes by itself, before then adding the salmon to the sheet-pan. The veggies will be crispier and caramalize more. I like to cook my salmon for a longer period of time than called for in the recipe, so cooking the ingredients together from the start was the way I chose to cook this recipe.
And one word of caution, do not rub your eyes with your hands after chopping the jalapeno pepper.
Heat oven to 400 degrees, and line a baking sheet with parchment paper. In a large bowl, toss brussels sprouts, scallions and jalapeno with 2 tablespoons oil to coat. Season with salt and pepper, then spread out on the prepared baking sheet.
Pat the salmon fillets dry, then season with salt and pepper and nestle them, skin side down, among the brussels sprouts. Roast, stirring the brussels spouts occasionally, until the brussels spouts are tender and the salmon is cooked through, 12-14 minutes. (The salmon is done when a knife slides through it easily and the fih flakes, or when an instant-read thermometer reaches 120 degrees.)
When the salmon's roasting, stir together the citrus juice, rice vinegar, soy sauce and 2 tablespoons water. (If you find it too puckery, add a little honey or more water.) Serve the sauce alongside the salmon and brussels sprouts for drizzing and dipping.