Make the Beef Grillades
To make the Creole spices, mix the paprika, cayenne, garlic powder, onion powder, dried oregano, and thyme.
Season the beef with salt and pepper. Season the flour with the Creole spices, and reserve 1/4 cup. Put the remaining 1-3/4 cups flour in a large, shallow bowl, and then dredge the beef in the flour, shaking off the excess.
Heat the rendered bacon fat or butter in a large skillet over medium-high heat. Cook the cutlets until golden brown, about 2 minutes on each side, making sure not to overcrowd the pan (you might need to cook in batches). Set aside the cooked cutlets on a paper towel–lined plate.
Add the onions to the same pan, lower the heat to medium, and cook until the onions are a deep mahogany color, about 10 minutes. Add the celery, bell peppers, and garlic, and cook for another 5 minutes. Add a tablespoon of the reserved seasoned flour to the pan and mix well.
Add the tomatoes and beef stock to the pan and bring to a boil. Reduce the heat to low and stir in the thyme, red pepper flakes, bay leaf, and Worcestershire sauce; return the beef cutlets to the pan. Cover and simmer for 45 minutes, or until the meat is fork-tender. Discard the bay leaf. Add hot sauce to taste and more salt and pepper as desired.
To serve, put a heaping spoonful of Cheese Grits on a serving plate, top with 2 or 3 pieces of beef, and spoon the sauce over the meat. Garnish with scallions.
Make the Cheese Grits
In a large saucepan over high heat, bring 5 cups of salted water to a boil while slowly whisking in the grits. Reduce the heat to medium low; cover and cook for 25 to 30 minutes, stirring occasionally and making sure the grits aren’t sticking to the bottom of the pan; adjust the heat to low if the grits are cooking too quickly.
Remove the cooked grits from the heat and stir in the butter, mascarpone or cream cheese, and grated cheese. Season with salt to taste and serve warm.