Peel and wash potatoes, slice in half and place in a large pot with cold water. Bring to a boil and cook until soft.
Add chopped carrots, onion and garlic in a pan over medium heat with a splash of olive oil. Sauté until slightly softened (about 4-5 minutes).
Add ground beef and sausage and brown (about 5-7 minutes).
Deglaze the pan with white wine and add in tomato paste, Worcestershire and beef broth. Continue to stir occasionally for 20 minutes as the meat mixture absorbs most of the liquid.
Meanwhile, preheat oven to 350 degrees.
Once potatoes are softened, drain and add in melted butter and some milk. Mash until smooth, adding more milk if necessary. Season with salt to taste.
In a casserole dish, add the meat mixture and then layer on top the mashed potatoes. Top with grated cheese (I like using mozzarella) and pop into the oven for 25 minutes.
Option to finish under the broiler for a minute or two to get the cheese nice and golden on top.