Kielbasa and Sauerkraut

Bahan-bahan (4 porsi)

• 1 tablespoon olive oil
• 1 pound kielbasa (or smoked sausage sliced diagonally, ¾-inch)
• 2 tablespoons unsalted butter
• 1 medium white onion (sliced)
• 2 cups sauerkraut (drained*)
• ¼ cup chicken broth (or water)
• ½ teaspoon dried oregano
• ¼ teaspoon black pepper