Brown the lean ground beef in a skillet over medium heat. Drain excess grease and add the taco seasoning and water, then simmer 5 minutes.
Spray a nonstick skillet with cooking spray. Cook the onion and garlic for 2 minutes, then stir in the cauliflower rice, tomato sauce, and cumin. Cook for 5 minutes, then stir in the cilantro.
In a small bowl, mix the Greek yogurt, light mayonnaise, chipotle sauce, garlic powder, and salt until smooth.
Heat a nonstick skillet over medium-low heat. Add a tortilla and sprinkle 1/4 cup of cheese evenly over it. Cover with a lid and let it cook until the cheese is melted. Remove the tortilla from the pan.
Repeat with the second tortilla and remaining cheese.
Place beef, cauliflower, sour cream, and chipotle sauce onto the cheesy side of each tortilla. Fold sides inward and roll tightly.
Place seam-side down in a skillet and toast until golden and slightly crisp.