Creamy Southern Shrimp and Cheese Grits

Bring water to a boil in a large saucepan and slowly whisk in grits; reduce heat to medium-low and simmer until thickened and tender, 5 to 7 minutes, stirring occasionally. Stir farmers cheese, goat cheese, and American cheese into grits until cheese has melted. Set grits aside and keep warm. Melt butter with vegetable oil in a large skillet over medium heat. Cook and stir tomato, 2 green onions, and garlic in the hot skillet until the vegetables are tender, 5 to 7 minutes. Stir in bacon drippings until combined. Cook and stir shrimp with vegetables until bright pink, about 5 minutes; season to taste with salt and black pepper. Mix grits into shrimp mixture and stir in half-and-half until smooth. Simmer the mixture to blend flavors, about 5 minutes, and add sherry. Simmer 3 more minutes before adjusting salt and black pepper. Garnish with sliced green tops of 1 green onion before serving.