Preheat the Oven: Turn your oven on to 400F (200C). Put a piece of parchment paper on a large baking sheet. This makes cleanup so easy later.
Season the Potatoes: Put your halved baby potatoes in a bowl. Toss them with 1 tablespoon of olive oil, garlic powder, thyme, salt, and pepper. Spread them out on one side of your baking sheet.
Start the Roast: Put the potatoes in the oven for 10 minutes first. They need a little head start because they take longer to cook than the fish.
Add the Rest: Take the baking sheet out carefully. Place your salmon filets right in the middle. Put the trimmed asparagus on the other open side.
Flavor Everything: Drizzle the rest of the olive oil over the asparagus. Add a little salt and pepper to them. Rub the salmon with olive oil, then sprinkle on the paprika, garlic powder, salt, and pepper. Top each piece of fish with a fresh lemon slice.
Bake Until Flaky: Put the pan back in the oven. Bake for about 12 to 15 minutes. You will know the salmon is done when it flakes easily with a fork. The potatoes should be golden and the asparagus tender.
Serve Warm: Sprinkle some fresh parsley over the top. Serve it up hot and enjoy every clean, delicious bite!