Place whole potatoes in a medium-size saucepan and cover with cold water. DO NOT peel or cut the potatoes. We don’t want the potatoes to absorb too much water because then that water will be released in the form of bubbles during the frying process and the oil will splatter. Turn heat to medium-high and cook until tender (about 20 to 25 minutes). Drain potatoes and move to a bowl. Wait until they’re cool enough to handle and discard their skins.
Season potatoes with salt and pepper, and mash until you have a smooth paste. It won’t look exactly like a puree, but more like a potato paste. Set aside.
Heat about ½ cup of oil in a large skillet over medium-high heat. Adding the rest of the oil as needed.
While you are waiting for the oil to heat, slightly warm the tortillas one by one in a hot griddle, in order to make them more pliable. Cover them with a kitchen napkin.
Now, add about 2 tablespoons of the mashed potatoes over half of each tortilla and fold. Secure the sides of the tortilla with two toothpicks. Sometimes, I don’t use the toothpicks, but that requires some skill of firmly pressing down the edges while frying; if this is your first time making them, and to be on the safe side, use the toothpicks.
Place the folded taco into the hot oil, and cook for about one and half minutes per side, until golden brown and crispy. Since you will be working in batches to make your potato tacos, have a large plate ready and covered with paper towels to absorb the excess oil. Repeat the process until you finish cooking all the tacos.