Add the water and salt to a deep saucepan or stock pot. Bring it to a boil, and then add the grits. Reduce the heat to medium low and cook the grits for 25-30 minutes or until creamy and smooth, stirring occasionally. Adjust seasoning to taste and stir in the butter and cheese. Continue to stir until melted. Keep warm until ready to serve.
In a small bowl, whisk together the olive oil, rice wine vinegar, lime juice, chili powder, cayenne pepper, crushed red pepper and a dash of salt and pepper. Pour the mixture into a gallon-sized zip bag and add the shrimp. Close tightly and coat the shrimp evenly with the mixture. Set aside.
Heat the oil in a large sauté pan over medium heat. Add the shrimp and sauté until pink and cooked through, about 4-5 minutes. Remove from heat and stir in the corned beef.
Serve the shrimp and corned beef on a bed of grits. Sprinkle with parsley and enjoy immediately!