This recipe can be made on the grill, with the bacon and onions done in a cast iron skillet or grill plate. I included a stovetop version below, in case you’re staying indoors!
Oven Method
If you don’t have a grill or if the weather’s not right, you can make your chivito steak sandwiches indoors in the oven. To make these inside, prepare them in a large cast iron skillet or a cast iron grill plate. Heat the skillet or grill plate on your stovetop. When hot, proceed with the recipe as written, starting with the bacon, followed by the onions, then finish with searing the steak.
Next, place the steaks on a foil-lined baking sheet and top with bacon, onions, and cheese. Flash the steaks under a hot broiler to melt the cheese, then place them on the dressed buns and add the additional toppings as described above.