Heat a medium skillet over medium-high heat.
Add the 1 pound ground turkey to the skillet and cook, breaking it up with a spatula, until no longer pink and cooked through, about 6–8 minutes.
Stir in the homemade taco seasoning and 4 ounces tomato sauce; reduce heat to medium and let the mixture simmer for 2–3 minutes to combine flavors.
While the turkey simmers, halve the 3 avocados and remove the pits; scoop a little flesh if needed to make room for the filling.
Spoon the seasoned turkey mixture into each avocado half.
Top each stuffed avocado with shredded cheddar cheese, a dollop of sour cream, sliced olives, and chopped tomatoes as desired, then serve immediately.