In the same skillet, discard all but 1 tablespoon of the bacon drippings. Add oil and heat over medium-high heat.
Season scallops with salt and pepper. Sear scallops in skillet for 2 minutes on each side until caramelized and opaque. Be sure not to over crowd the pan; you may have to do in 2 batches.
To serve, top with bacon and onions.