Certain foods—among them fava beans, angelica flowers, orange blossoms and leaves, rose petals, fenugreek, grilled foods, dried lime, quince, saffron and walnut—have bitter flavor qualities, which are used to accentuate a certain astringency or drying character in some Persian dishes. Bitterness in food acts as a seasoning, bringing out earthy flavors and balancing acidity and sweet flavors. Bitterness in wine comes from grape tannins, oak tannins and alcohol, which can taste bitter. Bitterness in both wine and food offer some health benefits, according to recent research studies. So bitter is good, and certainly the combination of Cabernet Sauvignon with a lamb and fava bean braise is a very good example of good taste, good health and good pairing. Look for tannic reds such as Cabernet, Shiraz, Merlot and old-vine Zinfandels or Italian Barolos when pairing bitter foods with wine. A rich, oaky, high-alcohol Chardonnay will also do well.