Heat the vegetable oil in a skillet over medium-high heat. Add the shallots and mushrooms, and saute until soft. Remove and set aside.
In the same skillet, heat the olive oil over medium-high heat. Add the steak and sear on each side for about 2 minutes, or enough to leave the insides pink and juicy. Remove steak from heat, but leave the juices in the pan.
Lower the heat to medium. Return the mushrooms and shallots back to the skillet; add the soy sauce and stir until the vegetables are well coated.
Slice the steaks into bite-size pieces and pour the mushroom mixture over the meat. Serve immediately, with steamed rice.