Season the trout fillets with thyme, salt, and pepper.
In a large skillet or cast iron pan, add olive oil and place over medium-high heat.
Add the seasoned steelhead trout fillets, skin side up, and cook for two minutes per side.
Reduce the heat to low, and add the butter, lemon juice, capers, and sliced garlic. Cook for another 5 minutes, or until the fish flakes with a fork. You can also check the internal temperature using a meat thermometer until it reaches 145°F.
Carefully remove the fish from the pan (the skin may stick to the pan, which is fine) and drizzle with the pan sauces over the top.
Notes
Leftovers: Keep covered in the fridge for 3 days or the freezer for 2 months.