1. 1. Peel and finely chop the shallots, wash, dry, and chop the parsley.
2. 2. Bring the chicken broth to a boil.
3. 3. In a thick-bottomed pot, melt 15g of butter. Add the shallots and cook them for 3 minutes until golden.
4. 4. Add the cooked and peeled chestnuts (reserve 4 for decoration). Coat them well with the fat and let them cook for another 3 minutes.
5. 5. Pour in the hot chicken broth and let it simmer for 10 minutes.
6. 6. Using a blender, finely blend the chestnuts with the cooking liquid and add the heavy cream. Season with salt and pepper. Blend again until you obtain a very smooth velouté.
7. 7. In a large skillet, melt the remaining butter. Sear the scallops and the remaining 4 chestnuts for 1 minute on each side. Season with salt and pepper.
8. 8. Pour the velouté into bowls, add the scallops, sprinkle with chestnut pieces and parsley before serving.