Bring 3 cups water, milk, and 2 teaspoons salt to a boil in a large heavy saucepan over high. Whisk in grits, and cook, whisking constantly, 45 seconds, scraping bottom and sides as needed. Return to a boil; cover and reduce heat to medium-low. Cook grits until tender, 20 to 25 minutes. (For a looser texture, whisk in 2 to 4 tablespoons water halfway through cooking.)
Meanwhile, melt 2 tablespoons butter in a large skillet over medium-high. Add half of the shrimp, 1/2 teaspoon salt, and 1/4 teaspoon pepper. Sauté until shrimp are almost pink, 5 to 6 minutes. Toss with 1/2 tablespoon lemon juice, and transfer to a plate. Repeat with 2 tablespoons butter and remaining shrimp, salt, pepper, and lemon juice.
Add chives and remaining 2 tablespoons butter to grits. Top with shrimp, tomatoes, and Salsa Verde.
Made this for guests last night....sure beat the cured salmon recipe that was on the same page as this recipe. I made it exactly as posted and i wouldn't change a thing!! Everyone agreed it was delicious. My grits were a little soft for my taste so I think i would use a little less water but i was the only one who felt that way. This was really delicious and i will make it again.