Season salmon with salt and pepper. Place in a baking dish.
Toss asparagus with a little olive oil (or butter), salt, and pepper. Arrange around the salmon.
Melt butter in a pan, add garlic (cook 1 min). Stir in lemon zest and juice, plus red pepper flakes if using.
Pour garlic lemon butter over salmon and asparagus.
Bake for 12–15 minutes, until salmon flakes easily and asparagus is tender-crisp.
Serve hot — no rice or grains needed!
