fill the potatoes and vegetables in a big casserole dish.

for the sauce you need to heat the oil in a pot that fits at least 1,5 liters and add the onions. Don´t brown them, just glaze them.

when they are glazed, add the garlic and the rosemary and cook another 1-2 minutes.

Add the tomato paste, stir and let it cook until it starts to stick to the bottom of the pot. By doing this you get out the bitter compounds out of the tomato paste.

deglaze with a sip of wine and add the tomatoes and the basil.

Stir and let cook for 10-15 minutes, stir occasionally.

Now add sugar, salt and pepper to taste and pour the sauce over the vegetables in the baking dish. If you like, blend the sauce with an emersion blender. I do that because my son doesn´t like tomato pieces in his food.

Sprinkle the parmesan on top and bake at 180° degrees celsius für around 45 minutes. It´s done when the potatoes are soft.