Cook the large pasta shells according to the package directions.
Drain the pasta shells and rinse them gently with cool water.
Preheat the oven to 350°F.
In a large skillet over medium heat, cook the lean ground beef until fully browned.
Drain any excess fat from the skillet.
Add the freshly minced garlic to the cooked ground beef.
Sauté for 2 minutes, stirring frequently, until the garlic is fragrant.
Add the taco seasoning mix and salsa to the skillet.
Stir until the ground beef is evenly coated with the seasoning and salsa.
Cut the softened cream cheese into pieces.
Add the cream cheese to the skillet.
Stir continuously until the cream cheese is fully melted and incorporated into the beef mixture.
Spray a 9x13-inch baking pan with nonstick cooking spray.
Arrange the cooked pasta shells in the prepared baking pan with the openings facing upward.
Using an ice cream scoop or large spoon, fill each pasta shell with the taco beef mixture.
Sprinkle the shredded Mexican or Fiesta cheese blend evenly over the stuffed shells.
Place the baking pan in the preheated oven.
Bake for 15 to 20 minutes, or until the cheese is melted and bubbly.
Remove the baking pan from the oven.
Allow the shells to rest for 2 minutes before serving.
Sprinkle the chopped green onions over the top.
Serve warm.