Heat a skillet over medium-high. Add the ground beef and break it up with a spatula. Cook until no pink remains. Drain any excess fat.

Sprinkle the taco seasoning over the meat. Add a splash of water and stir. Simmer for 1 to 2 minutes, then remove from heat.

In a large bowl, stir together the cooked rice, sour cream, nacho cheese sauce, and chipotle sauce until smooth. Fold the seasoned beef into the rice mixture.

Lay a tortilla flat. Sprinkle a little cheddar and mozzarella down the center. Add a portion of the beef-rice mixture on top of the cheese. Fold the sides in, then roll the tortilla tightly. Repeat with the remaining tortillas.

Warm a clean skillet over medium-low. Brush each rolled burrito lightly with butter or oil. Place seam-side down and grill until golden brown, about 2 to 3 minutes per side. Flip and press gently with a spatula for even browning.

Transfer burritos to a cutting board. Let them rest for 2 minutes, then slice in half and serve with your favorite sides.