To prepare a steak whisky peppercorn sauce, you'll first need to prepare your steak. Cut the steak into 12 inch (1.27 centimeters) thick slices and season with salt and pepper. Heat the olive oil in the skillet over medium-high heat until shimmering. Add the onion and cook until softened, about 3 to 4 minutes. Remove the pan from the heat and add the garlic. Cook until fragrant, 2 to 3 minutes, stirring frequently. Stir in 2 tablespoons of the red wine vinegar and 2 teaspoons each of thyme, oregano, and paprika. Simmer, whisking occasionally, until the wine is reduced by half and the onions are tender, 10 to 15 minutes more.