01 - Combine rice, water, and salt in a medium saucepan. Bring to a boil, reduce heat to low, cover, and simmer for 15 minutes until water is absorbed. Remove from heat and fluff with a fork.
02 - Heat olive oil in a small skillet over medium heat. Add black beans, cumin, and salt. Stir and cook for 3 to 4 minutes until heated through. Set aside.
03 - In a large skillet over medium-high heat, cook ground beef and onions until browned and onions are soft, about 6 to 8 minutes. Drain excess fat if necessary. Add garlic, chili powder, cumin, smoked paprika, oregano, salt, and pepper; stir for 1 minute. Mix in tomato paste and broth; simmer 3 to 4 minutes until thickened. Remove from heat.
04 - Warm tortillas until pliable. Layer rice, beans, and beef filling in the center of each tortilla. Top with cheese, salsa, and sour cream if desired.
05 - Fold in sides and roll burritos tightly with seam down. For crispier texture, toast in a skillet for 1 to 2 minutes per side. Garnish with chopped cilantro if desired and serve immediately.