1. Season sirloin with salt and pepper. Heat a large, wide shallow pan over medium-high heat. Swirl in 1 tablespoon oil, add steak in a single layer, and cook, turning a few times, until browned and medium-rare, about 5 minutes. Transfer to a plate.

2. Add remaining 1 tablespoon oil to pan and cook vegetables, stirring occasionally, until onion is golden in places, about 5 minutes. Stir in tomato paste and cook 1 minute. Add spices and cook until fragrant, 15 seconds. Add broth; bring to a simmer. Cover, reduce heat, and simmer until carrots are crisp-tender, about 10 minutes. Return sirloin and any accumulated juices to pan; cook until warmed through, about 1 minute. Remove from heat. Season with salt and pepper; sprinkle with mint. Serve over couscous.