In a bowl, combine the thinly sliced beef, minced garlic, cumin powder, paprika, salt, black pepper, soy sauce, and red wine vinegar. Toss the beef to ensure it’s evenly coated with the marinade. Let it marinate for at least 30 minutes.
Heat the vegetable oil in a large skillet or wok over high heat.
Once the oil is hot, add the marinated beef slices to the skillet. Stir-fry the beef for 2-3 minutes until it’s browned on the outside but still tender on the inside. Remove the beef from the skillet and set it aside.
In the same skillet, add the sliced red onion, yellow and red bell peppers, and jalapeño pepper. Stir-fry these vegetables for 2-3 minutes until they begin to soften and become slightly charred.
Return the cooked beef to the skillet and toss it with the sautéed vegetables.
Add the tomato wedges and stir-fry for another 1-2 minutes until the tomatoes just start to soften.
Finally, sprinkle the fresh cilantro over the stir-fry and give it a quick toss to incorporate the cilantro’s aromatic flavor.
Serve your Lomo Saltado hot, over a bed of cooked white rice, garnished with additional cilantro leaves.