Toss the stew meat in flour, salt and pepper.  Brown in oil over medium heat in a heavy casserole pan (with a lid). Add the chopped onion and stir cooking for 5 minutes.  Add the thyme and red wine and cook over bubbling heat for 15 minutes or until the red wine is mostly absorbed.  Add the beef stock, chestnuts, and carrots.  Add salt and pepper to taste. Cover and cook over low heat bubbling for 1 ½ hours checking the liquid and stirring from time to time.  After 1 hour add 10-15 whole red grapes and cook another 30 minutes. The stew should have thick liquid, not dry and not covered in broth at the end of cooking.  While the stew is cooking peel the potatoes, cut them in half and slow boil in salted water until they can be pierced with a fork, 10-15 minutes.  While the potatoes are boiling heat the butter and sauté the scallions.  Add cream, 1 t sea salt (or more) and several grinds of black pepper.  Add the cream, stir and turn off the heat. Drain the potatoes when done, and, while hot, press the potatoes through a ricer.  Return to the hot pan and add the butter scallion mixture.  Mix well and cook over low heat to thicken the purée.  Serve with the stew garnished with a heavy sprinkle of chopped parsley and a simple green salad.  The La Jasse will rock your world!!