Get the pan smoking hot so the halibut won’t stick. Let it get a good sear on the first side, which will also help it release.
Season halibut with salt and pepper.
Heat oil in a large skillet, preferably cast iron, over medium-high heat until beginning to smoke. Cook halibut until golden brown, 6–8 minutes. Turn and cook until other side of fish is golden brown, about 4 minutes longer.
Add butter, thyme sprigs, and garlic to pan and cook, tilting pan and spooning butter over fish, until halibut is opaque throughout and butter is brown, about 2 minutes.
Add capers and toss in butter to warm through.
Divide halibut among plates and spoon butter sauce over.
2 servings
* The % Daily Value (DV) tells you how much a nutrient in a serving of food contributes to a daily diet. 2,000 calories a day is used for general nutrition advice.