Soak the dried porcini in hot water for 30 minutes
Gently fry some rosemary in a bit of olive oil for about one minute, so that it flavours the oil, then discard it.
dd the root vegetable a little pinch of cumin and gently cook about half an hour
Now cook the spuds in boiling salted water
Filter the porcini water, and put it in a blender add water to make 500ml, add the porcini, the tomato puree, the red onion and blend until smooth. Add this to the veg pan.
Add the tinned brown lentils an let it cook for 30 minutes
Make a mash with the potatoes, butter and milk
Now in an oven proof dish make a base layer with the Puy lentils, cover them with the vegs and finally top it all with the mash.
Bake for 30 min in the over at 190 C