Preheat the oven to 425°F (220°C) °F.
On a large sheet pan, toss the halved Brussels sprouts with 2 tablespoons olive oil, ½ teaspoon garlic powder, salt and black pepper.
Spread them cut-side down in a single layer and roast for 12 minutes while you prepare the salmon and sauce.
In a small saucepan, melt 3 tablespoons butter with 2 teaspoons olive oil over medium heat.
Add 6 garlic cloves (minced) and cook for 30 seconds until fragrant.
Stir in ½ cup honey, 1 tablespoon water, 3 tablespoons soy sauce, 1 tablespoon sriracha, and 2-3 tablespoons fresh lemon juice. Simmer for 1–2 minutes, then remove from heat.
Pat 4 salmon fillets dry and season with ½ teaspoon kosher salt, ½ teaspoon black pepper, and ½ teaspoon smoked paprika.
After the Brussels sprouts have roasted for 12 minutes, remove the pan from the oven.
Push the sprouts to one side and place the salmon fillets on the other side.*
Pour the honey garlic sauce generously over the salmon.
Return the sheet pan to the oven and bake at 400°F for 10–12 minutes, or until the salmon is cooked through and flakes easily with a fork. The sauce will thicken and coat the salmon beautifully.
Spoon pan sauce over the salmon and sprouts. Garnish with parsley or sesame seeds if desired. Serve hot.