In a bowl whisk to combine the sugar and spices. Rub the mixture all over the ribs and transfer them to the fridge.
Place the ribs in the oven or over indirect heat on your BBQ. Let smoke or bake for 4 hours. Start misting the ribs with red wine vinegar every 15 minutes in the last hour of cooking.
Once the beef is on the grill, make the onions. Place the onions in a bowl and add the lemon juice, olive oil, sumac, and salt.
Stir to combine, cover, and transfer to the fridge. Let the onions chill for a minimum of 2 hours. Or until the onions turn pink.
Place the white beans and garlic in a food processor and blitz. Stream in the olive oil and lemon juice.
Transfer the white bean puree to a bowl and add the yogurt. Stir to combine. Taste and season with additional salt accordingly.
Arrange the beef ribs on a platter and cover them with onions. Top with fresh mint leaves, if desired. Serve immediately alongside the white bean puree.