Brown the ground beef in oil in a large skillet over medium‑high heat, breaking it up, until no pink remains, 6 to 8 minutes. Drain fat if desired. Stir in taco seasoning and water, simmer until thickened, about 2 minutes. Remove from heat.

Warm tortillas one at a time in a dry skillet over medium heat, 30 seconds per side, or microwave stacked with a damp paper towel for 45 to 60 seconds.

Spread 1/4 cup refried beans down the center of a tortilla, top with about 1/2 cup beef, 2 tablespoons nacho cheese, a dollop of sour cream, and 1/4 cup shredded cheese.

Fold in the sides, then roll up tightly from the bottom, tucking as you go. Place seam‑side down in the skillet and toast over medium heat 1 to 2 minutes until golden, then flip and toast the other side 1 minute more. Serve hot.