In a medium bowl, combine the soy sauce, red wine vinegar, Worcestershire sauce, cumin, and black pepper. Add the beef strips and toss to coat. Let marinate for at least 15 minutes (or up to 1 hour in the refrigerator).

While the beef marinates, prepare your vegetables: cut the red onion and tomatoes into thick wedges, and slice the aji amarillo peppers (or bell pepper). Mince the garlic.

Heat 1 tablespoon of vegetable oil in a large wok or skillet over high heat until shimmering. Add the marinated beef in a single layer (cook in batches if necessary to avoid overcrowding). Sear for 1-2 minutes per side until browned but still slightly pink inside. Remove beef from the wok and set aside.

Add the remaining 1 tablespoon of vegetable oil to the wok. Add the red onion and aji amarillo (or bell pepper) strips. Stir-fry for 2-3 minutes until they begin to soften.

Add the minced garlic and tomato wedges to the wok. Stir-fry for another 1-2 minutes until the tomatoes are slightly softened but still hold their shape.

Return the seared beef to the wok. Add the cooked french fries. Toss everything together quickly to combine and heat through, about 1-2 minutes. Season with salt to taste.

Remove from heat. Stir in the fresh cilantro and parsley just before serving.