Preheat oven to 375.
Place the potatoes on a baking sheet and bake until tender when pierced with the tip of a knife, 40-45 minutes depending on the size of the potatoes. Let cool completely, then diced and set aside. We leave the skins on.
Reduce the oven temperature to 350.
In a bowl, combine the potatoes, corn, bell pepper, onion and spinach.
Add 1 cup of the enchilada sauce and mix well. Season with salt and pepper to taste, and set aside.
Pour about 1/2 cup of the remaining enchilada sauce into a 9 x 13 inch baking dish. It should just cover the bottom.
In a wide frying pan over medium heat, warm the remaining enchilada sauce. Once at a time, dip each tortilla into the warm sauce, allowing it to warm just enough to become pliable. Then, place it in the prepared baking dish, and spoon about one-twelfth of the potato mixture along its center. Roll it up and arrange it in the dish, seam side down. Repeat with remaining tortillas and filling. The dish should be tightly packed.
Pour any sauce remaining in the pan over the enchiladas. Sprinkle with the soy cheddar.
Bake until heated through and the cheese is melted, 20-25 minutes. Serve directly from the dish.