In a food processor, whirl 1/4 lb. shrimp until not quite a smooth paste. Add remaining 1/4 lb. shrimp and pulse to chop coarsely. Pulse in chives. Divide mixture into 24 pieces. Roll each piece into a ball and place in parchment-lined steamers (see â€œHow to Steam Dim Sum,â€� below). Steam dumplings until cooked through, about 10 minutes. Serve immediately.
How to Steam Dim Sum: Measure your steamer basket and choose a pot with a diameter at least 2 in. wider. To keep dumplings from sticking, cut a circle of parchment paper 1 in. smaller in diameter than the basket (so steam can flow up around the edges) and fit it in. Pour enough water into pot to come 1 in. up side and bring to a boil over high heat. Fill basket with dim sum first, then set it in the pot. Cover and cook, adding hot water as needed.