If using frozen scallops, allow to thaw in the fridge. Then rinse the scallops and place on a paper towel and pat dry.
Let the scallops sit for a few minutes and pat dry again. Then remove the muscle on the side of the scallops (sometimes this is already done).
Heat a skillet over medium high heat, adding butter and olive oil. Season one side of the scallops with salt and pepper.
Once the skillet is hot, place scallops, seasoned side down into the skillet. Salt and pepper the other side of the scallops. Let cook for 2 minutes and then carefully flip over to cook the other side.
Once the sides of the scallops are opaque, they are cooked through. There should be a golden brown sear on both sides. Remove from the skillet and serve immediately.
Tips for cooking scallops: a raw scallop will be somewhat translucent. As it's cooking, you can watch the sides become more opaque, this is how you know they are done. It shouldn't take more than 4 minutes to cook the scallops through on both sides.
Even if cooking from frozen, always rinse your scallops under cold water before preparing.