Dice the onion into a small dice.
Add the cooking oil or butter to a deep pot, add the onions, and sauté until soft and slightly golden brown.
Add the ground beef and cook with the onions, crumbling it up as you go.
Add the dry seasonings including the packets of Sazon and the chili seasoning packets. Sauté for 10 minutes.
Add the diced tomatoes, green chilis, ketchup, and water. Bring to a simmer and simmer for 15 minutes.
Drain and add the canned potatoes and the water, bring to a boil again, reduce heat to a low simmer and simmer one hour.
Stir this occasionally, but do not cover.
If you like you can also put this all in a slow cooker at this point and cook low and slow 6 hours.
Turn off the heat and let the stew sit for 15 minutes before serving.
Top with cheese, onions, and sour cream.
