Heat a skillet on medium heat.Add diced onions and garlic. When they start to stick to the pan add a few tablespoons of water (up to ¼ cup) and stir with a silicon spatula. These can cook for a few minutes while you prepare the potatoes.Add bite sized potatoes to the skillet plus ¼ cup of water and cover with a lid. Cook for 10 minutes, check for sticking half way through and add water and stir if needed. Prepare the rest of the veggies.Add the bell pepper and jalapeno, stir and add more water if needed then cover with a lid and cook for 10 more minutes but check it after 5. At this point the potatoes should be softened enough to bite or cut with a fork.Check for doneness. If potatoes and peppers are cooked through add the tomatoes, cover with the lid and remove from heat. Let them sit for 5 minutes.