Sofrito Flank Steak

Ingredients

• 1 onion, cut into one-inch pieces
• 1 green pepper, cut into one-inch pieces
• 1 red pepper, cut into one-inch pieces
• 1 bunch fresh cilantro
• 6 garlic cloves
• 1 tablespoon olive oil
• 2 teaspoons salt
• 1 teaspoon fresh ground pepper
• 1 lb flank steak, scored on both sides