1. Melt butter in medium saucepan over medium-high heat. Add onion, pepper, garlic and 1 teaspoon Cajun seasoning; cook 5 to 8 minutes or until vegetables are tender and begin to brown, stirring occasionally.
2. Stir in milk; bring to a boil. Slowly add grits, stirring constantly. Reduce heat; cover and simmer 4 to 5 minutes or until mixture is thickened and creamy, stirring occasionally. Remove from heat; add cheese. Let stand 1 minute. Stir until cheese is melted. Season with salt, as desired. Keep warm.
3. Meanwhile, press remaining 2 teaspoons Cajun seasoning onto beef Steak. Place steak on grid over medium, ash-covered coals. Grill, covered, 11 to 15 minutes (over medium heat on preheated gas grill 13 to 16 minutes) for medium rare (145°F) to medium (160°F) doneness, turning occasionally.
4. Carve steak lengthwise in half, then crosswise into 1/8 to 1/4-inch thick strips. Season with salt and pepper, as desired. Place grits in shallow bowl; top with beef. Serve with hot sauce, as desired.