Preheat oven to 350˚F. Set potatoes in large pot of boiling water. Cook until fork tender, 12-15 minutes. Drain and set aside.
While potatoes cook, heat skillet over medium heat. Add beef and onions and cook until beef is browned about 8-10 minutes. Add garlic, salt, and pepper cook for 1 minute.
Add corn and bbq sauce to beef. Remove from heat and set aside.
Mash potatoes with cream cheese, butter, salt, black pepper, white pepper, and milk or cream..
Pour beef mixture into 9”x13” baking dish and top with potatoes in even layer. Top with cheese and bake for 25-35 minutes or until cheese is browned around edges of pan.