In a small combine all ingredients for the homemade rub and stir until combined.
Remove the membrane from the back of the ribs be sliding a dinner knife under the membrane and over the bone. Left and loosen the membrane until it tears. Grab the edge of the membrane with a paper towel and pull it off. It might come off in one big piece of you will have to remove it in smaller pieces. This is ESSENTIAL so make sure you take it off.
Spread yellow mustard evenly over the ribs covering completely. Next, spread the dry rub over the ribs covering completely. Wrap in saran wrap so they are completely covered. Place in fridge to rest a minimum of 2 hours, but we do it overnight for best results!
Prepare your smoker according to manufacture's directions to a heat of 225 F degrees. We use apple wood chips when making these ribs.
Once the smoker is preheated to 225 degrees F place ribs, bone side down, on the smoker and let smoke for 3 hours at 225 degrees F.
Mix together 1/2 c. apple juice and 1/2 c. water in a spray bottle and spritz ribs with mixture every half hour.
After 3 hours remove ribs from smoker but leave smoke on at same temperature.
Lay two pieces of tinfoil out on counter (enough to wrap ribs in). Evenly smear the 2 Tbp yellow mustard down the middle of foil about 4 inches wide. Place butter slice evenly between the foil pieces down the middle of foil. Next lay the ribs on the foil, bone side done. Tightly seal the foil. Place ribs back in the smoker at 225 degrees F for 2 hours.
After 2 hours has passed remove the ribs from the smoker. Remove the ribs from foil. Mix together ingredients for the finishing sauce in a mixing bowl. Coat ribs with finishing sauce and place back on the smoker for 1 hour.
Remove from smoker and brush with sauce again and serve!