Brown the ground beef in a pan with the French onion soup mix.
Add some minced onion (optional).
Line a baking sheet with foil and spray with non-stick spray.
Mix the cooled ground beef with mayo and shredded cheddar cheese.
Layer the buns on the prepared baking sheet.
Top with the beef mixture and cover with the remaining buns.
Cover the sliders with foil.
Bake directly on the oven rack at 350°F for 30 minutes.
Let cool for 10 minutes, then slice and serve.
