Grill beef to desired doneness, and allow to cool.
While beef is cooling, stir together fish sauce, lime juice, kecap manis, garlic, ginger, cilantro, sesame oil, and chili oil; mix in the green onions and shallots. Adjust seasoning to your taste.
Cut beef into bite-sized pieces. In a large bowl, toss with onion, tomatoes, cucumber, and chili peppers. Pour in the dressing, and toss to coat.