First place the meat in a tall pot and cover it with water and add the whole onion and the salt. Bring the water to a boil over high heat. Reduce heat to medium and simmer covered for at least 2 to 3 hours. The meat should pull apart. Remove the meat from the pot and set aside to cool. When cool enough to handle, shred meat with your hands into thin strips. Add oil to the pan. When the oil is heated add the shredded beef to the pan, when you notice that the beef is getting crisp toss the beef to the other side and add the 3 sliced onions and peppers and saute. For the Mojo, combine lemon juice, garlic, and extra virgin olive oil. When the beef is crisp on both sides, pour in Mojo just enough to wet.
Recipe courtesy of Nicholas Vazquez, Executive Chef, Azucar, Edgewater, NJ