Brown the ground beef with the taco seasoning, chopped onion and peppers. Once cooked, transfer to a large mixing bowl and add salsa. Stir well.
Cut each biscuit into six pieces. Place half the biscuit pieces into a sprayed lasagna dish and cover with half the beef mixture. Sprinkle with cheese. Repeat layers. Sprinkle the top with the green onion.
Loosely cover with foil and bake for 30 minutes at 350 degrees F (if making immediately). If refrigerated, increase bake time to 45 minutes, then remove foil and bake for an additional 15 minutes. Allow to rest 5 minutes before serving. Top with a dollop of sour cream, if desired.