Season fish with salt and pepper. Heat 1 tablespoon butter and olive oil in a large skillet over medium heat. Brown fish on one side, about 3 – 4 minutes. Flip over and cook for 2 – 3 minutes or until just cooked, but not overcooked. Remove fish and keep warm. In a container, combine gingerroot with next three ingredients. Add to the pan and increase heat to medium-high. Reduce liquid to just a few tablespoons, add basil and orange zest and cook for 1 minute more. Whisk in remaining chilled butter until melted. Spoon sauce over cooked fish.