Slice then cut onions. Slice the half onion and then cut the slices in half, as shown.
Add the butter to a skillet and turn on medium heat. Once the butter melts, add the bell pepper and onions. Cook until the bell pepper and onion soften but not limp. Remove the pepper and onion and set aside for now.
Cut the sirloin in strips (doesn't have to be perfect). Season the meat with salt and pepper. Brown in the same skillet that you cooked the bell pepper and onion in (keep that flavor going). **Using a meat mallet will create more tender cuts of the steak** NOTE: I have updated the recipe to call for strips and not "cubes", but you can do it either way.
Combine the browned meat, bell pepper, onion and the stewed tomatoes in the same skillet or move to a deeper pot, like I did. Add 1 tbsp of worchestershire sauce and a little more pepper to taste.
Bring to a boil and then turn the heat to low and simmer for 2-3 hours. Let it all the flavors combine.
Notes
ITEMS/INGREDIENTS USED IN RECIPE - If you are interested in any of the items I may have used (or are similar to the items I used) in making this recipe, I have listed all or some of them above within the post. NOTE: These links are affiliate links of which I receive a small commission from the sale of certain item. This does not affect your price, it remains the same.