Boil diced potatoes in salted water until fork-tender, about 12–15 minutes. Drain well.
Mash potatoes with milk, butter, garlic powder, salt, and pepper until smooth and creamy.
Stir in shredded cheese and bacon (if using).
Lay out the tortillas and spoon the cheesy mashed potatoes into the center of each. Roll up burrito-style.
Heat a bit of oil or butter in a skillet over medium heat. Fry each burrito seam-side down until golden and crispy, about 2–3 minutes per side.
Serve warm with sour cream, salsa, or your favorite dipping sauce.