Bring water, salt, and 1 tablespoon butter to a boil in a 3- to 4-quart heavy saucepan, then add grits gradually, stirring constantly with a wooden spoon. Reduce heat and cook at a bare simmer, covered, stirring frequently, until water is absorbed and grits are thickened, about 15 minutes. Stir in 1/2 cup milk and simmer, partially covered, stirring occasionally to keep grits from sticking to bottom of pan, 10 minutes. Stir in remaining 1/2 cup milk and simmer, partially covered, stirring occasionally, until liquid is absorbed and grits are thick and tender, about 20 minutes more. (Grits will have a soft, mashed-potato-like consistency.) Stir in pepper, cheese, maple syrup, and remaining tablespoon butter or bacon grease.
Cook bacon in large skillet, then add butter to melt. Add onions and cook until translucent. Stir in flour and create a thick paste. Add in beer, bring to boil then stir in shrimp and cook until liquid is reduced by half. Ladle over cheesy grits.
Combine all ingredients and serve atop Shrimp & Grits.