Pat scallops dry on paper towels. Season with salt and pepper.
Heat a cast iron skillet or large pan over medium-high heat. Add avocado oil and wait until it is hot.
Lay scallops in the pan, leaving space so as not to crowd them. They should sizzle immediately. Cook for 2 minutes without touching them.
Flip the scallops and immediately add the butter and garlic. Cook for another 90 seconds to 2 minutes, spooning the melting butter and garlic over the scallops, until they are browned on both sides and opaque throughout, then remove from the pan to a plate.
Serve immediately with the pan juices drizzled over top.