In a large skillet, heat 1 tablespoon of olive oil over medium heat until it shimmers slightly.
Add the chopped onion to the skillet and sauté for about 3-4 minutes, until the onion becomes translucent and fragrant.
Add the lean ground beef to the skillet with the sautéed onion. Break apart the beef using a wooden spoon or spatula, and cook until browned and no longer pink, about 6-8 minutes.
Once the beef is fully cooked, sprinkle in the taco seasoning and stir well to combine. Add a splash of water if necessary. Cook for an additional 2-3 minutes to allow the flavors to meld.
While the beef is finishing up, arrange the Tostitos Scoops on a serving platter. Once the beef mixture is ready, fill each scoop with the seasoned beef.
Set out an array of optional taco condiments, allowing guests to customize their Bite-Size Tacos to their liking!