Preheat your oven to 400°F.
Meanwhile, in a small mixing bowl, add the soy sauce, lemon juice, sriracha, and honey to make a quick marinade. Slice your salmon into small cubes, about 1 cubic inch in size, and add the salmon cubes to the marinade to soak.
Prep your vegetables by rinsing and chopping broccoli and rinsing and slicing shiitake mushrooms. Add them to an 18 x 26-inch baking sheet.
Drizzle the olive oil over the broccoli and shiitakes and use clean hands to toss to make sure the vegetables are evenly coated in the oil. Roast for 8 minutes at 400°F.
After 8 minutes, remove the vegetables from the oven and add the salmon and marinade to your baking sheet with them. Toss with kitchen tongs or a spoon (careful, the baking sheet is hot!) to coat the broccoli and mushrooms in the marinade.
Put your baking sheet back in the oven for 7-8 more minutes, until vegetables are roasted, and salmon is cooked through (the optimal internal temperature of salmon is 145°F).