Add garlic and onion, cook until softened, 2 minutes. Stir in tomato sauce, chicken broth, cumin, and salt. Bring to a boil, reduce heat, cover, and simmer for 18-20 minutes until rice is tender. Fluff with a fork and set aside.
While rice cooks, heat olive oil in a large skillet. Add onion and cook until translucent, 2-3 minutes. Add garlic, cook 1 minute, then add ground beef. Cook until browned, 5-7 minutes. Stir in cumin, chili powder, smoked paprika, oregano, salt, and pepper. Add tomato sauce and beef broth, simmer until thickened, 4-5 minutes. Remove from heat.
In a small saucepan, combine black beans, cumin, chili powder, and salt. Heat until warmed through, about 3-4 minutes. Mash lightly if desired.
Warm tortillas. Layer beef mixture, beans, rice, cheese, lettuce, and tomatoes on each. Fold sides and roll tightly. Toast in skillet for 1-2 minutes per side for crispiness. Cut in half, garnish with sour cream and cilantro.
Notes
For extra flavor, add chopped fresh cilantro on top before serving.