Put chestnuts in a pot with cold water and bring to a boil. Let it cook on low for about 20 minutes, until the chestnuts are cooked through. Drain and peel the chestnuts, crush them into smaller pieces and set aside.
Preheat oven to 180°C / 360°F. Slice pumpkin into large strips or chunks. Peel and place in a baking tray. Sprinkle with olive oil and season with salt & pepper. Mix so as to cover every piece of pumpkin. Place in heated oven and bake for about 20 minutes, until the pumpkin becomes tender. Remove from oven and set aside.
Peel and thinly slice onion and garlic cloves. In a pan or pot, heat 1 tbs of olive oil on medium. When heated, add sliced onion and gently fry until translucent. Add garlic and stir. Then, add farro, mix in well with the onions and pour over 1 dcl of dry white wine. Let the farro absorb the wine, then stir and add vegetable stock. Season with salt & pepper and let it cook on low, stirring occasionally. If the farro absorbs all of the stock and is still not cooked, add warm water as needed. Cook for about 30 minutes until tender.
While the farro is cooking, puree the pumpkins with a stick blender or in a food processor.
In a pan, melt butter, then add chestnuts and pan-roast them in butter until golden brown. Set aside.
When the farro is almost cooked, add in the pumpkin puree and butter-roasted chestnuts, add chopped parsley and chives to taste and grated parmesan, then serve.