In a large skillet, heat the oil over medium high heat for 2 minutes, then brown the mince (ground beef) until no pink remains, drain, then set aside.
Wipe out the skillet. Melt the butter over medium high heat until it is foamy, then add the onion and carrot and sprinkle with salt. Sauté for 8 minutes, then add the garlic and cook until fragrant.
Add the black pepper and the tomato paste. Cook for 2 minutes, stirring constantly. Sprinkle on the flour and cook for 2 minutes.
Deglaze the pan by pouring in a bit of beef broth, using a spatula to scrape the browned bits off the base of the pan, then gradually pour in more beef broth while stirring.
Add the Worcestershire sauce and the drained mince (ground beef) back into the skillet. Mix the together and add a bit more beef broth to get it the right consistency.
Simmer uncovered for 15 minutes to cook down the liquid into a nice gravy, add the salt. Simmer for another 5 minutes, taste, and adjust seasonings.
While it is simmering, cook the 6 peeled and quartered tatties (potatoes) until fork tender with 1 teaspoon kosher salt and 2 bay leaves. Drain and air dry in the strainer. Return the tatties (potatoes) to the pot. In a small saucepan, over medium heat, heat up ½ cup of milk and 2 tablespoons of unsalted butter. Mash the tatties (potatoes) and then add the warmed milk and butter mixture. Add salt and black pepper to taste.
Serve the mince and tatties together with boiled peas and enjoy.