In a medium saucepan, bring broth, milk, butter, garlic, and salt to a boil over medium-high heat. Gradually whisk in grits; reduce heat to medium-low. Cover and cook, whisking occasionally, until grits are thickened, about 20 minutes. Remove from heat; gradually whisk in cheese. (Whisk in 2 to 4 tablespoons warm milk if grits become too thick.) Serve immediately.
Recipe by Louisiana Cookin' at https://louisianacookin.com/slow-cooker-grillades/