It is tomato time. Heaped in piles at the farmers market, they hold the promise of the true taste of summer. The heirloom varieties are my favorites, as much for their quirky names as their flavor. Arkansas Traveler, Brandywine, Green Zebra, Jubilee, they are lumpy and bumpy, cracked and misshapen. Fanned out in multicolored sort-of-circles for a tomato, basil and mozzarella salad or dripping from a tomato sandwich, what could be better? Inner beauty is more important than outer beauty when it comes to tomatoes.