Creamy Stone-Ground Grits

Bring water and milk just to a simmer in a 4- to 5-quart heavy saucepan. Meanwhile, cover grits with water in a large bowl and whisk vigorously. Let stand 30 seconds, then skim any chaff that has floated to surface with a fine-mesh sieve. Drain grits well in a fine-mesh sieve and whisk into simmering milk mixture.

Reduce heat to low and simmer grits, partially covered, stirring often with a heatproof rubber spatula, until grits are tender and thickened to the consistency of loose oatmeal, about 1 1/4hours (stir more toward end of cooking to avoid scorching). If grits become too thick before they are tender and creamy, thin with hot water (about 1/2 cup).

Stir in cream, butter (if using), and salt. Remove from heat and keep warm, covered, up to 20 minutes.