Mix the meat, egg, bread crumbs, beer and garlic salt. Shape the mixture into 3/4-inch balls. Prepare the batter by combining baking mix, beer and egg. Heat oil in a metal fondue pot to 375 degrees F. Spear the meatballs with a fondue fork, dip into the batter and cook in hot oil to the desired doneness, about 2 minutes. Serve with both sauces.
NOTE: These meatballs can also be cooked without the batter. For mustard sauce, combine mayo, mustard and onion. Refrigerate.
For horseradish sauce, combine sour cream, horseradish and Worcestershire. Refrigerate.