Place a large skillet over medium-high heat. Add the oil if using, then crumble in the ground beef. Cook, stirring occasionally and breaking up the chunks with a wooden spoon, until the meat is completely browned and no pink remains, about 5-7 minutes.

Carefully drain any excess grease from the skillet to avoid oily tacos.

Reduce the heat to medium-low. Stir in the taco seasoning and water or broth. Let the mixture simmer gently for 5-8 minutes, stirring occasionally, until most of the liquid has been absorbed, leaving the meat moist and flavorful.

While the meat simmers, prepare the chip bags. Locate the sealed end of each small bag and carefully slice it open with scissors about halfway down the side to create a larger opening.

Gently crush the chips inside the bag slightly to create more surface area for toppings.

Place the seasoned ground beef in a slow cooker (set to Warm) or a serving dish to keep it hot. Arrange toppings nearby.

Take an open chip bag. Spoon 2 large scoops of the hot taco meat into the bag. Top with shredded cheese, lettuce, tomatoes, salsa, and sour cream. Shake gently to mix, then enjoy!