Preheat oven to 375. Place cubed butternut sqush into a large bowl, add salt, pepper, sugar, balsamic vinegar and 2 tablespoons of olive oil and toss to coat. Spread mixture on a baking sheet and bake for 1 to 1 1/2 hours until done. Remove from oven and set aside. Once the squash are in the oven season the beef with salt pepper. Sprinkle flour on top and coat well. Heat the the remaining olive olive in a large dutch oven, add the meat to the dutch oven and saute in batches until browned on all sides. Remove beef from the pan and set aside in a bowl. Add onion, rosemary and garlic to the pan. Saute until tender and translucent. Deglaze the pan with the wine, scraping up any browned bits on the bottom of the pan. Add the stock and return the beef to the pan with any collected juices. Simmer for 1 1/2 hours or until beef is fork tender. Add one teaspoon of reduced basalmic vinegar and cooked squash to beef and simmer for 10 - 15 minutes. Serve with bread or wide pasta noodles. Note: if you can't find reduced balsalmic vinegar you can take 1/4 cup of regular balsalmic vinegar and boil it down until you have a tablespoon.