To make this Provençal-inspired sauce, we bloom saffron threads in water to draw out their flavor and aroma. The golden liquid then is stirred into a base of sautéed garlic and tomato paste that has been browned to develop depth of flavor. Saffron adds inimitable notes of earth, flowers and minerals, but is quite pricey. The sauce still will be delicious made without, as it derives ample flavor from orange zest, pepper flakes and fresh thyme. If omitting the saffron, simply add ¾ cup water to the browned tomato paste along with the orange juice. This recipe yields enough sauce to dress 1 pound of pasta, however, it’s also delicious over seafood; chopped fresh flat-leaf parsley or basil are ideal herbal garnishes.