First, there was wonton soup. Then came tortellini in brodo. Now, thanks to Szifra Birke, I’ve found the joys of kreplach. Years ago, Szifra produced the poignant documentary “Browsing Through Birke’s” (now out on DVD). It’s the story of her parents, Nathan and Sally, who emigrated from Poland and founded Birke’s clothing store, a Lowell, Massachusetts, institution. This documentary had me laughing, blubbering, and feeling instant affection for these extraordinary people. Always looking to connect through food, I asked Szifra if her mother had a signature recipe. She wasted no time in sharing Sally’s prized kreplach and the deeper story behind it. Born Sura Dymantsztajn in Lodz, Poland, Sally no doubt learned to make…