Add half and half and water to a large pot over medium high heat and bring to a boil. Add some salt to salt liquid.
Once liquid starts boiling, briskly stir in grits and bring heat down to low and cover with lid. Cook according to instructions on back of package (about 20 for stone ground) stirring twice during this time to maintain smoothness. They should be completely tender and thick.
These can also be done with Quick grits in a pinch. It takes about 5 minutes to make.