Add vegetable oil to the instant pot and set to sauté. Cook the sliced steak until browned in batches. Avoid overcrowding. Remove steak and place it on a plate or in a bowl.
Continue until all of the meat is browned. Add onions and bell pepper to the instant pot. Sauté for 5 minutes and then add the minced garlic and jalapeño. Sauté for an additional minute.
When finished, let the pressure naturally release for 10 minutes and then manually release pressure. Garnish with cheese, sour cream, cilantro, and tortilla chips.