“Melt-in-your-mouth yumminess nom nom nom” is how my niece Katie (who shares not only my name, but my taste in nail polish colors) described this dish. She had just moved to Los Angeles and was missing some of the comfort food her Pah Pah (Chinese for “grandmother”) used to make. Most of the dishes we regard as comfort food in our family are the simplest, like this Stir-Fried Beef with Tomato. The tender and succulent beef is quickly stir-fried with juicy, ripe tomatoes, on