Place grits in 4-cup microwave-safe bowl. Add water; stir to combine. Microwave on HIGH 4 minutes, stirring after 3 minutes, or until thickened as desired.
In large skillet, cook ham slices over medium-high heat about 1 minute per side or until browned. Remove from skillet; cover to keep warm.
Drain fat from skillet, reserving 2 teaspoons in skillet. Add coffee to skillet. Cook over medium heat, stirring rapidly to loosen browned bits of ham from bottom of skillet. Add water to reach desired consistency if mixture is too thick. Cook for an additional 2 to 3 minutes, stirring occasionally. Spoon over hot grits.