Pre-heat the oven to 180°C.
Peel and roughly chop the potatoes. Place in a saucepan and boil for about 20 minutes or until softened.
Meanwhile, heat 2 tablespoons of olive oil in a saucepan and sautée the grated onions, carrots, courgettes, mushrooms and minced garlic for a few minutes until golden. Add the chopped rosemary and thyme and cook for a few more minutes.
In a separate saucepan or deep frying pan add another tablespoon of olive olive oil and cook the minced meat until it is browned. Stir constantly to ensure that all parts of the meat are cooked. Drain off the excess fat at the end.
Add the sautéed carrots, courgettes, mushrooms, garlic and onions into the minced meat. Add the tomato puree and pour over the chicken stock. Then add a dash of Worcestershire sauce and season with salt and pepper to finish.
Bring to the boil and gently simmer for 20 minutes or so, until the meat is cooked and the mixture has thickened. Spoon the mixture into individual ramekins or into a 10 inch pie dish.
Return to your boiled potatoes. Drain and mash them with butter, sour cream and cheese (if using). You can add more butter if you feel it needs some.
Spoon the potato mixture over the meat mixture in the pie dish or ramekins, and finish them off with a drizzle of olive oil.
Bake in the oven for 25 minutes or until the top is golden. Serve with steamed tenderstem broccoli or your favourite crunchy salad.