Preheat oven to 400°F and line a large baking sheet with parchment paper.

In a small bowl, mix together the garlic powder, onion powder, oregano, and paprika. Set aside.

In a large bowl, toss the potatoes with 2 tbsp olive oil, about ½ of the seasoning mix, and salt and pepper. Spread out on the baking sheet and bake for 8 minutes.

Meanwhile, brush the salmon filets with the Dijon mustard and salt and pepper.

After 8 minutes, push the potatoes to one half of the pan then add the asparagus and salmon to the other half of the pan and drizzle both with remaining olive oil and sprinkle with remaining seasoning mix. Toss asparagus to coat well.

Return to the oven for 15-20 minutes, or until potatoes are fork tender and salmon is cooked to your liking. *Note if your salmon filets are very thin, they will cook much more quickly and may not need the full cook time and can be added to the pan later.*