In a medium bowl, whisk together soy sauce, Worcestershire sauce, lemon juice, minced garlic, salt, black pepper, sugar, and water. Set aside.

Place sliced sirloin beef in a shallow dish and pour the marinade over it. Cover with plastic wrap and refrigerate for at least 30 minutes.

In a large skillet, heat vegetable oil over medium-high heat. Add the sliced onions and sauté for 3-5 minutes until they soften.

Carefully add the marinated beef to the skillet, reserving excess marinade. Cook for 5-7 minutes until the beef is tender and browned.

Pour the reserved marinade into the skillet and let it simmer for an additional minute until the sauce thickens. Remove from heat.

Plate the Filipino Beef Steak and garnish with black pepper and fried garlic chips. Serve immediately with steamed rice.