Preheat the oven to 375°F (190°C).

Wash, peel, and cube the potatoes, then cook in salted water until fork-tender (10-15 minutes). Drain and mash until smooth.

Heat olive oil in a skillet over medium heat, then sauté onion for about 5 minutes until translucent. Add garlic and cook for an additional minute.

Combine mashed potatoes, black beans, corn, cumin, paprika, salt, and pepper in the skillet and stir for 5 minutes.

Spread green chili sauce at the bottom of a baking dish. Fill corn tortillas with the potato mixture, roll, and place seam-side down in the dish.

Pour remaining green chili sauce over the enchiladas, cover with foil, and bake for 20-25 minutes. Uncover for the last 5 minutes.

Let cool slightly, garnish with cilantro and avocado, and serve.