1Place potatoes in a small saucepan and cove with cold water by 1 inch. Add 1 tbsp. salt and the vinegar. Bring to a boil reduce to a simmer and simmer until soft about 8 minutes. Drain and let rest 5 minutes to dry.
2Place 1 inch of oil in skillet and heat it on high until very hot. With tongs drop one tortilla in hot oil. Turn once and remove to paper towel. This should only take about a minute each. Repeat with the other 3 tortillas. Set aside.
3Dump out most of the oil leaving a small amount in skillet. Add the Chorizo and cook breaking it up until done. Remove with slotted spoon to a plate and add the potatoes to the oil in pan. Cook tossing occasionally until crisp and golden about 10 minutes. Add the scallion and jalapeno tossing until softened. Add the Chorizo back in pan and season with salt and pepper to taste.
4Transfer to plate and keep warm. Wipe out skillet and add the 1 tbsp of oil. Add the eggs and cook until whites are done. Remove from heat.
5To assemble the tacos.
Place the Chorizo and potato mixture on top. Then place 1/4 cup of salsa on each tortilla. Sprinkle with Cilantro, Cotija Cheese and sour cream. Top with fried egg and sprinkle some fresh ground pepper on egg.