Preheat your oven to the temperature specified on the vegetarian pie packaging. Place the pie on a baking tray and cook according to package instructions, typically around 25-35 minutes, or until golden brown and heated through.

While the pie is baking, peel and chop 600 grams of potatoes into chunks. Boil them in salted water until tender, about 20 minutes.

In another pot, add 400 grams of sliced carrots. Boil until tender, approximately 10-15 minutes, depending on the thickness of the slices.

Drain the potatoes and mash them with 50 ml of milk and 25 grams of butter. Season with salt and pepper to taste.

Drain the carrots once cooked. Optionally, toss them in a pan with a teaspoon of butter, a sprinkle of sugar, and a pinch of salt for a glaze, cooking for an additional 2-3 minutes over medium heat.

Serve the baked vegetarian pie with a side of mashed potatoes and glazed carrots. Garnish with fresh herbs if desired.