Season the lamb with salt, pepper, garlic powder, and onion powder.
Place a cast-iron, stainless steel, or other heavy-bottomed frying pan over medium-high heat. Add the oil and allow to become very hot (a drop of water should sizzle).
Lay the seasoned lamb in the skillet and let sear for 2 minutes to develop a golden-brown exterior. Flip the lamb over and sear the other side for an additional 2 minutes.
Reduce the heat to medium and return the steaks to the first side. Cook the lamb for 4-6 more minutes, occasionally spooning some of the pan juices over the top of the lamb to add more flavor and expedite cooking.
Flip the lamb steaks over again and continue to pan-fry until they reach an internal temperature of 145 degrees, about 4 minutes.
Insert an instant-read thermometer into the middle of the thickest part to check the temperature. Transfer the lamb steaks from the pan and onto plates or a cutting board. Let rest for 5 minutes before serving so the internal juices settle.
To serve, garnish with the fresh thyme.