Cook pasta in boiling water, 8-10 minutes.
While pasta is cooking, brown beef over medium heat until cooked through.
Add in cream cheese, salt and chili powder, mix together and simmer for 5 minutes.
Once pasta is cooked, toss pasta in melted butter.
Fill pasta shells with beef and place in 9"x13" pan.
Pour taco sauce over shells, then cover with foil and bake at 350 for 15 minutes.
Once cooked, add cheese and tortilla chips on top of pasta shells, and bake an additional 15 minutes without foil.
Remove from oven and top with green onions, sour cream, olives, and any other toppings. Enjoy!