In a large bowl, combine the rinsed pinto beans with enough water to cover them by 2 to 3 inches. Allow the beans to soak overnight.
The next day, drain the beans and transfer them back to a large pot. Add fresh water to cover the beans, followed by the diced tomatoes with green chilies, bacon pieces, diced onion, chili powder, cumin, and garlic powder. Give everything a good stir.
Bring the mixture to a boil over medium-high heat. Once boiling, lower the heat and let the beans simmer for about 3 hours. Remember to check on them occasionally, adding more water if necessary to keep them submerged.
After 3 hours, mix in the chopped cilantro and salt to taste. Let the beans continue to simmer for about 1 more hour, or until they're tender and reach your preferred consistency.
If the bean mixture becomes too thick while cooking, simply add hot water, 1 tablespoon at a time (up to 1/4 cup), until you achieve the desired consistency.