These are a popular choice in tapas bars. This version uses flavorful sirloin with a quick and easy recipe for Spain's famous almond-and-red pepper sauce.

Serves 6 as an appetizer; 4 as a main course

Romesco Sauce:

• 3/4 cups 1/2-inch cubes stale bread
• 1/3 cup Marcona almonds
• 2 small garlic cloves, chopped
• 1 small tomato, seeded and coarsely chopped
• 1 cup drained roasted red bell peppers
• 2 1/2 teaspoons sherry vinegar
• 3/4 teaspoons fine sea salt
• 1/4 teaspoon smoked paprika (pimentón)
• 2 tablespoons extra-virgin olive oil

Beef Skewers:

• 1 tablespoon extra-virgin olive oil
• 1 clove garlic, minced
• 1 teaspoon sweet paprika
• 1 teaspoon ground cumin
• 1/2 teaspoon fine sea salt
• Pinch cayenne or hot paprika
• 1 1/4 pound beef sirloin, trimmed of fat and cut into 1-inch cubes

1. For the sauce, combine bread and almonds in a food processor and process until finely ground. Add garlic, tomato, peppers, vinegar, salt and smoked paprika; process until puréed, stopping to scrape down the sides of the bowl once or twice. With the machine running, pour the oil through the feed tube. Transfer to a bowl.
2. For the beef, soak 12 small (6-inch) bamboo skewers in cold water for at least 30 minutes before cooking. In a large bowl, whisk together oil, garlic, sweet paprika, cumin, salt and cayenne. Add beef cubes, toss to coat, and set aside for at least 10 minutes, or refrigerate up to 1 day.
3. Heat a grill pan over high heat or prepare an outdoor grill for medium-heat cooking. Thread 3 to 4 beef cubes on each skewer, being sure that the tip is covered by beef. Grill, turning occasionally, until beef is browned, 4 to 5 minutes on an outdoor grill and 6 to 7 minutes on a grill pan. Serve the skewers hot with room temperature Romesco sauce.