Place the cubed potatoes in a small sauce pan and fill the sauce pan with water until the potatoes are just covered. Place potatoes on stovetop over high heat and bring to a boil. Once the water is boiling, cook potatoes until they are just fork tender, about 5 minutes. (You do not want them to be too tender, otherwise they will get mushy when combined with the chorizo.)
Meanwhile, heat a large skillet over medium-high heat with 1 tablespoon of olive oil. When oil is hot, add the chorizo and onion to the pan. Brown the chorizo, breaking up the meat with the edge of a spoon, until it is cooked through, about 10 minutes. When the chorizo is cooked through, use a slotted spoon to transfer to a paper-towel lined plate. Set aside and reserve the fat in the bottom of the skillet to cook the potatoes.
Drain the potatoes and transfer to the same skillet where the chorizo was cooked, over medium heat and evenly spread the potatoes in the bottom of the skillet. Gently sauté potatoes with a rubber spatula, tossing occasionally until potatoes are golden, about 3-4 minutes.
Add chorizo back into the skillet. Gently toss until all of the ingredients are evenly combined. Taste and add salt, if needed (this really just depends on the chorizo you use). Remove from heat and cover to keep warm.
Meanwhile, heat a skillet over medium heat and spray with non-stick spray. Fry eggs until done to your liking. (You can really top your tacos with any-style eggs you want or even serve them eggless.)
Serve the chorizo con papas inside of warmed torillas and topped with an egg. Garnish with cilantro and serve with lime wedges.