In a saucepan, bring the water and milk to a boil. Add the salt and slowly add the grits and return to a boil, stirring constantly for 1 minute. Reduce the heat, cover, and cook for 3 minutes. While stirring the grits add the butter and stir until butter is melted. Cover and cook for 3 to 5 minutes, or until the grits are thick and creamy. Remove from heat and set aside.
Saute the onions in the remaining tablespoon of butter for 1 minute. Add 1/2 cup cheddar and onions to grits and stir until the cheese is melted. Add the tomatoes and mix well. Stir in the beaten eggs. Pour the grits into a greased oven safe dish and bake for 40 minutes. Sprinkle remaining cheese over top during the last 5 minutes of cooking time
Notes
Grits are made from a less sweet, starchy variety of corn, such as dent corn. The corn goes through a type of processing that soaks the dried grains in lye or another alkali for several days, which removes the hard hull; the resulting grain is referred to as hominy. When purchasing grits, you will find hominy as well as white and yellow corn, instant and stone-ground varieties.
Food Fact: Grits are the official food of South Carolina.
History: The word "grits" is derived from an Old English word "grytt," which means coarse meal.
Polenta is an Italian version of grits. It's made from cornmeal, so it has a significantly different texture and flavor. It is prepared similarly and can look like grits, which is where the confusion may lie.
Origin: Even before the European explorers came West, the Indigenous peoples of North America were eating a dish of mashed corn, as corn was a prevalent crop.