Notes: If making up to 1 day ahead, cover and chill.
Prep and cook time: about 30 minutes
In a 2 1/2- to 3-quart pan over medium-high heat, frequently stir olive oil, onion, fennel, and garlic until onion is limp, about 5 minutes. Add chicken broth, white wine, tomato paste, thyme, and saffron or turmeric; bring to a boil. Reduce heat, cover, and simmer until vegetables are soft when pressed, about 15 minutes. Measure broth; if less than 6 cups, add more fat-skimmed chicken broth or water.