
Seared Steak with Blistered Tomatoes and Green Beans stars a simple-but-punchy vinegar-onion mixture spooned on top of sliced steak and roasted vegetables.
Heat oven to 450°F. On large rimmed baking sheet, toss green beans and tomatoes with 1 tablespoon oil and a pinch each of salt and pepper.
Roast until vegetables begin to brown, 10 to 12 minutes. Meanwhile, in medium cast-iron skillet on medium, heat 1 teaspoon oil. Season steak with 1/4 teaspoon each salt and pepper; cook with garlic until browned, 3 minutes per side.
Transfer skillet to oven along with vegetables and roast to desired doneness, 3 to 4 minutes for medium-rare steak. Transfer to cutting board and let rest at least 5 minutes before slicing in half.
In bowl, combine vinegar, remaining tablespoon oil and a pinch each of salt and pepper; stir in onion. Serve sliced steak with half of vegetables; spoon half of vinegar-onion mixture on top. Refrigerate remaining vegetables, steak, and marinated onions for lunch the next day.