Heat the olive oil and butter in a large oven-safe skillet over medium-low heat. Add the onion and cook, stirring often, for about 15 minutes or until softened. Stir in the potatoes, garlic, and smoked paprika.
Increase the heat to medium-high and continue to cook until the potatoes are just starting to brown, about 10 minutes. Remove from heat and pour in the broth.
Cover the skillet and place it in the oven. Bake covered for about 10 minutes (or until the potatoes are tender), then remove the cover and cook until the liquid has reduced into a thick sauce that coats the potatoes, about 15-20 minutes more. Season with salt and pepper to taste and sprinkle with parsley, if using. Serve with Spicy Romesco Sauce.
Notes
If you don't have an oven-safe skillet, no worries! Simply transfer the potatoes to a roasting dish before putting them in the oven.
Craving more veg-friendly recipes? Shop our collection of vegetarian and vegan cookbooks, including our new Vegan Thanksgiving and Vegan Christmas cookbooks!