Wash hands with soap and water.
Heat oven to 425 °F. Arrange rack in upper third of the oven.
Line rimmed baking sheet with foil. Place flank steak on baking sheet. Do not rinse raw meat. Wash hands after handling raw meat.
Gently rub garlic and lime under cold running water.
Combine garlic, lime juice, olive oil, paprika, cumin, salt and pepper in a small bowl. Pour marinade over steak and rub onto both sides. Wash hands with soap and water after handling raw meat.
Do not reuse marinades used on raw foods.
Gently rub cherry tomatoes and shallots under cold running water.
Spread cherry tomatoes and shallots over top of the steak and season with salt and pepper.
Roast in the oven until internal temperature reaches 145 °F on a food thermometer, usually about 15 minutes. Let rest for about 10 minutes, then slice and serve with melted tomatoes, shallots and warm tortillas.