In a small bowl, sprinkle the beef cubes with salt and pepper and then toss with the 2 tablespoons of flour. Heat a dutch oven or a pot with a lid over medium-high heat and add the olive oil. When hot, add the floured beef cubes and cook for about 5 minutes, or until golden brown. Remove the beef from the pot and set aside.
Add the onion, celery and bell pepper to the pot. Cook until softened and translucent, but not yet browning, about 5 minutes. Add the thyme and rosemary, squash, carrots,peaches, sweet potato, tomatoes, and beef broth. Bring to a boil, reduce heat to a simmer, add the beef back into the pot, along with any accumulated juices, and cover the pot. Cook over low heat for one hour, stirring occasionally.
Taste to check for seasoning, adding a few dashes of Worchestershire if desired, as well as additional salt and pepper as needed. Serve with fresh crusty bread for mopping up juices.