Prep all ingredients per the instructions above.
Make Salsa: Combine diced tomatoes, finely chopped onion, jalapeño pepper, minced garlic, chopped cilantro, and lime juice in a bowl. Mix well and season with salt and pepper to taste. Refrigerate the salsa for at least 30 minutes to let the flavors meld. Adjust seasoning if needed before serving.
Cook the Steak: Heat half the vegetable oil in a skillet over medium-high heat. Add the seasoned steak to the skillet and saute for about 3-4 minutes until nicely browned. Remove the steak from the skillet and set aside.
Cook the Onions and Peppers: In the same skillet, add the remaining vegetable oil. Add the sliced onions and bell peppers to the skillet and sauté until they become tender and slightly caramelized, about 5-7 minutes. Season with a pinch of salt and pepper.
Assemble the Burritos: Lay out the flour tortillas. Divide the cooked steak, sautéed onions, bell peppers, and shredded cheese evenly. Fold in the sides of each tortilla and then roll them up tightly to enclose the filling.
Warm the Burritos: In the same skillet or a clean pan, heat the burritos over medium heat for about 2-3 minutes per side or until they are heated through and the cheese is melted. You can optionally press them with a spatula to help seal the edges.
Mix the sparkling water and lemon.
Serve: Cut the warm burritos in half diagonally and place them on serving plates. Enjoy immediately with the homemade salsa and tortilla chips on the side. Serve with sparkling water.