Preheat oven to 425°F. Line or spray/grease a large sheet pan with foil or parchment paper.
Toss potatoes with 2 tablespoons of the olive oil, salt and pepper to taste, and 2 teaspoons of the herb blend. Arrange on a large sheet pan and bake in preheated oven for 20 minutes checking half way and giving them a shake.
In the meantime prepare the sauce for the salmon: In a small bowl whisk together melted butter, sriracha, honey, dijon mustard, and ½ teaspoon remaining herb blend and pinch of salt and pepper. Brush sauce onto salmon fillets.
Carefully remove hot pan from oven, push the potatoes over to one side of the pan and carefully arrange salmon fillets and tomatoes and asparagus on the sheet pan.
Drizzle asparagus and tomatoes with remaining 2 tablespoon olive oil, season with salt and pepper to taste
Carefully place pan back in the oven and cook for another 15 minutes until asparagus is fork-tender and salmon is cooked through. You’ll know they are cooked when the flesh is opaque and flakes easily. For a little extra char or colour feel free to broil or place under broiler for a couple minutes.
Serve immediately garnished with chopped parsley and lemon slices with a squeeze of lemon juice if desired over everything.
