Preheat oven to 400º F. Using a metal skewer or pearing knife, poke several holes into the flesh of the pumpkin, so there are evenly distributed holes around the body of the pumpkin. There should be a hole about every inch or so. Roast the pumpkin on a baking sheet or in an oven proof dish for about an hour. You will know it's done when it is very tender to the touch and you can tell it is soft through to the hollow center.
While the pumpkin is roasting, make your ragout. Heat the olive oil in a medium sized sauce pan. Sauté the mushrooms, garlic, and shallots until the mushrooms are brown and tender.
Add the vegetable broth, bring mixture to a boil, then reduce to a rolling simmer.
Take the sprigs of rosemary and roll them in your fingers, smashing them a little and bringing out the aroma of the rosemary oil, then throw them into the simmering mixture. Let simmer until the mixture reduces by one-third, about 20 or 30 minutes.
Mix the arrow root powder into the tablespoon of water until it is blended, and then add the arrow root mixture to the simmering mushroom mixture. The sauce should thicken up and take on a lovely translucent consistency.
Add the liquid aminos, and then taste for salt and pepper. Season to taste. The vegetable broth may have seasonings already so be careful not to over-salt the sauce.
When the pumpkin is ready, remove from the oven and let it sit until it is cool enough to handle with a dry tea towel. Cut the pumpkin in half and carefully scoop the seeds from the inside and discard, leaving the flesh intact. Then cut the halves into segments that are a good size for serving, quarters, or eighths usually.
Serve with the mushroom ragout on top. Serve with seared spinach, fresh vegetables, wild rice, or any of your other favorite healthy accompaniments. You might even try some cranberry relish with it, for a little bit of a holiday sweet finish.