In boiling water add your beans and let them cook for 3-5 min then reserve.
In a hot wok or pan add 2 tablespoons of vegetable oil then add the meat and seal 1 min per side, saute then reserve.
In the same pan add onions, Ají Amarillo paste, beans and let them cook for at least 3 min then add the meat back, saute and add cilantro, tomatoes, fried potatoes, soy sauce, vinegar a pinch of pepper, stir and it's good to go.
Notes
Some people add eggs to this preparation, as they go well with green beans.
The "ideal" size of the listed ingredients are "bite" size
Sauté requires a very hot pan and little oil, sauté in portions other wise you will end with a stew.