Preheat oven to 375°. Prep sheet pan with a silicone baking mat or parchment paper.
Slice half of the lemon into thin (¼") rounds, and cut the other half in half. Set aside.
Place salmon on center of sheet pan, skin side down, and drizzle olive oil over the top.
Sprinkle a healthy pinch of salt and pepper all over the salmon. If using thyme, place sprigs directly on salmon.
Next, cover the top of the salmon with 3 to 4 lemon slices, and place the lemon quarters on the sheet pan.
Bake for 15-18 minutes, until salmon is opaque pink, and the edges look a little bit crispy.
To serve, remove the sliced lemons and thyme, and squeeze one of the baked lemon quarters over top/serve on the side. Enjoy!