Ingredients
2 tablespoons olive oil
1 shell steak, 6 to 8 ounces
Coarse salt and ground pepper
1/2 small onion, thinly sliced
1 yellow bell pepper, quartered lengthwise and thinly sliced crosswise (ribs and seeds removed)
2 garlic cloves, thinly sliced
1/4 teaspoon dried oregano
3 tablespoons red-wine vinegar
2 tablespoons tomato paste
1/3 cup water
Preparation
In a small skillet, heat olive oil over medium heat. Trim and season steak with coarse salt and ground pepper; cook until desired doneness, about 2 minutes per side for medium-rare. Transfer steak to a plate; cover with foil to keep warm.
Make sauce: Add onion to pan; cook, stirring often, until starting to soften, about 3 minutes.
Add bell pepper, garlic, and dried oregano; season with salt and pepper. Cook until bell pepper is crisp-tender, about 5 minutes.
Add red-wine vinegar, and bring to a boil; continue boiling until almost evaporated, about 1 minute. Add tomato paste and 1/3 cup water; cook 1 minute more. Spoon pepper sauce over steak.