Combine boiling water and porcini, and set aside.
Heat oil in a large Dutch oven over medium heat; add the carrot and next 8 ingredients (carrot through rosemary). Cook 30 minutes or until browned, stirring frequently. Stir in the tomato paste, flour, salt, and black pepper; cook for 1 minute. Stir in porcini mixture and wine, scraping pan to loosen browned bits. Bring to a boil; reduce heat, and simmer 30 minutes. Strain through a colander into a large bowl. Drain well, pressing the vegetable mixture with the back of a spoon to remove as much sauce as possible. Return sauce to pan, discarding the solids. Bring to a boil, and cook until reduced to 2 1/2 cups (about 5 minutes). Stir in soy sauce and butter.