In a large Dutch oven, fry ground beef, bell peppers, onions, leeks and garlic until veggies are tender and no pink remains on the beef.
Cut beef down in small pieces with a hamburger chopper while frying.
Drain all grease.
Sprinkle GF flour over top of beef mixture and work into beef.
Cook 1-2 minutes.
Add salt, pepper, tomato paste, Worcestershire sauce, seasonings and beef broth.
Stir until tomato paste is worked into the mixture.
Add mixed vegetables, medley and asparagus and cook about 5-10 minutes at a simmer.
Turn off heat.
Spray two 9x13” glass baking dishes with cooking spray.
Pour meat mixture into prepared baking dishes.
Spread half of the mashed potato topping over each casserole and spread with a rubber spatula all the way to the edges.
Seal in the beef so there are no gaps.
Sprinkle paprika, garlic salt, dill weed, ¼ tsp. black pepper over top of each casserole.
Sprinkle 1 cup of cheddar cheese over top of seasoned of each casserole.
Sprinkle snipped chives over top of cheese on each baking dish.
Bake at 400° for about 30 minutes until top is lightly, golden brown.
Allow casserole to sit out about 10 minutes and set up before serving.