In the south of France, this spicy sauce is traditionally spread on toasted croutons and dipped into bouillabaisse. But its delicious flavors complement more than just fish soup. Try croutons and rouille with your favorite soup, or use the sauce as a sandwich spread or dip. If oil rises to the top during storage, stir or blend the rouille in a food processor before using.
1. Dissolve saffron in 1/2 cup boiling water. Pour water over bread, and let stand 30 minutes, or until soft and mushy. Mash with fork, then cool completely.
2. Place garlic cloves in bowl of food processor, and process until finely chopped. Add tomato paste, lemon juice, and cayenne, and process until smooth. Add saffron-soaked bread, and process 1 minute, or until no lumps remain. With motor running, add oil in slow, steady stream until mixture is emulsified into a mayonnaise-like sauce. Season with salt, if desired. Chill 1 hour before using, and store in fridge up to 1 week.