Begin by peeling and quartering the potatoes. Place these in a large saucepan, cover with cold water, and season with a pinch of salt. Bring the water to a boil over high heat.

Once boiling, reduce the heat to a simmer and allow the potatoes to cook until they are tender, which should take approximately 20 minutes.

After the potatoes are cooked, drain them and return them to the saucepan. Add the prescribed amounts of milk and butter. Using a potato masher, mash the potatoes until they achieve a smooth and creamy consistency. Season with salt and freshly ground black pepper according to your preference. Cover the saucepan with a lid to keep the mashed potatoes warm while you prepare the gravy.

In a large skillet, heat a drizzle of oil over medium-high heat. Add the ground beef and cook, stirring occasionally, until it is thoroughly browned and no longer pink. Carefully drain off any excess fat from the skillet.

To the same skillet, add the diced onion and minced garlic. Sauté for approximately 5 minutes, or until the onion becomes translucent and soft.

Sprinkle the flour evenly over the cooked beef and onion mixture, stirring constantly. Continue to cook for an additional 2 minutes to cook off the raw flour taste.

Gradually pour in the beef broth, stirring continuously to combine. Add the Worcestershire sauce. Scrape any browned bits from the bottom of the skillet to incorporate them into the mixture. Bring the gravy to a simmer and allow it to thicken, approximately 5 minutes of cooking time.

Should you choose to include peas and carrots, add them during the last few minutes of cooking the gravy. This will ensure they are heated through but retain their vibrant color and slight crispness.