In a large pot, add 3-4" of water and the halved or quartered potatoes and bring to a boil. Boil for 15 minutes or until the potatoes are fork tender.
Drain the potatoes in a colander and set them aside.
To the same pot, add 1 tablespoon of olive oil and heat over medium high heat.
Season the beef with salt and pepper. Add to the pot and brown for 2-3 minutes on all sides.
Add the sliced onions and saute for 5 minutes, or until the onions begin to soften.
Pour the sauce over the beef and onion mixture, then add the potatoes and stir to combine.
Bring to a low boil, then reduce the heat, cover, and simmer for 10 minutes.
Garnish with a sprinkle of chopped peanuts, a few sprigs of cilantro, and some sliced Thai chilis or red jalapeno (for some extra heat, if desired), serve, and enjoy!