In a bowl: combine brown sugar, salt, mustard, garlic, paprika, and pepper.
Clean and pat the ribs dry with a paper towel. Place the Rack of Ribs meat side down on the cutting borad. Remove the unattractive chewy skin membrane from the back of the ribs and discard.
Coat both sides of the ribs with the rub and marinate for at least 30 minutes.
Cover the ribs with aluminum foil. Place ribs on a baking sheet. Cook for 3 ½ hours or until fork tender.
In a sauce pan: mix all the ingredients together. Bring to a simmer and turn down the heat to low. Cook for 10 minutes or until sauce has reduced by half.
Remove the ribs from the oven. Turn the oven up to 450°F (232°C). Remove/fold back the foil. Then debone the meat (discard bones).
Then, generously coat the ribs on both sides with BBQ sauce. Bake for 15 minutes. Note: St. Louis style ribs: bake for 20 minutes. Cut the ribs to the same length as the hoagie bun.
Assemble:1.) Toast Buns 2.) Smear BBQ sauce on the bottom of the bun 3.) Add ribs meat4.) Garnish with sliced onions & pickles 5.) Slather on a bit more BBQ sauce 6.) Cap with top bun