In a saucepan over medium heat, warm the oil and swirl to coat the bottom of the pan. Add the carrots, onions and cook, stirring occasionally, until softened, 10 to 12 minutes.
Add the canned tomatoes, including the puree. Add the broth, and bring it to a boil. Reduce the heat to low and simmer, uncovered, for 20 minutes to blend the flavors.