Cook grits according to package directions. Stir in tomatoes, cheese, 4 Tbsp butter, and garlic salt. Cover and keep warm.
Meanwhile, cook bacon in a large nonstick skillet over medium heat 5 to 6 minutes or until crisp. Remove bacon with a slotted spoon, reserving drippings in skillet. Drain on paper towels.
Add 2 Tbsp butter to skillet with drippings over medium heat. Add bell pepper, garlic, and 2 tsp Creole seasoning; cook 2 minutes. Add tomato paste; cook, stirring, 2 minutes. Add wine; cook 2 minutes. Stir in broth; bring to a boil, reduce heat, and simmer 5 minutes.
Sprinkle shrimp with remaining 1 tsp seasoning. Add shrimp to skillet and cook 3 minutes or just until shrimp are done. Stir in lemon juice, sprinkle with onions.
Serve shrimp mixture over grits, sprinkle with bacon.