Barbecued Baby Back Ribs

This recipe was given to me by my good friend Lindsay.  
I really love ribs.  These are flavorful, tender, fall off the bone, saucy, awesomeness.  They are easy to make in that the cooking is done in the slow cooker then the ribs are place under the broiler to get the sauce nice and sticky-toasty the way ribs on the grill would be.  
So Yummy!

2 Tbsp. brown sugar
4 tsp. kosher salt
4 tsp. chili powder
2 tsp. paprika
2 tsp. black pepper (I used less since my older son is a heat-wimp)
2 tsp. garlic powder

1 medium red onion
1/2 c. carbonated cola
2 slabs pork baby back ribs (about 4 lbs. total), rinsed, patter dry and trimmed
1 c. purchased barbecue sauce

1.  Combine the brown sugar, salt, chili powder, paprika, pepper and garlic powder for the rub in a small bowl.  Thoroughly coat ribs with the rub, using all of the mixture.
2.  Add onion and cola to a 4-6 quart slow cooker.  Place ribs on top, cutting to fit if necessary.  Cover; cook until ribs are tender, on high heat setting for 3 1/2 - 4 1/2 hours or on low-heat setting for 6-7 hours.
3.  Preheat broiler to high with oven rack 6-8 inches from the heating element.  Transfer ribs to a foil-lined baking sheet; brush ribs with sauce.  Broil ribs until sauce caramelizes, about 5 minutes.