Cut off the top of the pumpkin and clean out the seeds and place it on a cookie sheet.
In a skillet add the oil and then the onions, and celery. Sauté for a few minutes and then add the ground beef and begin to cook. Cook until it is browned and then turn the heat too low.
Add the soy sauce, brown sugar, drained mushrooms, and cream of chicken soup. Simmer for 10 minutes.
While it simmers bring 1 1/2 cups water to boil and then add the minute rice stir, cover, and remove from heat.
Then add the cooked rice and the water chestnuts (not drained) into the mixture and then spoon the mixture into the pumpkin.
Place the top on the pumpkin and place in an oven preheated to 350 for 45 minutes to 1 hour. Then remove from oven and serve.