Heat avocado oil in a skillet over medium heat.
Add ground beef and break it up with a spoon. Cook until browned, about 6–8 minutes.
Add taco seasoning and a splash of water. Stir and simmer until thickened.
While the beef cooks, chop the romaine lettuce, halve the tomatoes, cube the avocado, shred the cheese, and chop the green onions.
In a large bowl or meal prep containers, layer the romaine, seasoned beef, cheese, tomatoes, avocado, and green onions.
Top with salsa and sour cream. Add crushed tortilla chips or pepitas if desired.
Serve immediately or store components separately for later.