Spratelloides delicatulus, the delicate round herring a.k.a the blue sprat, is a type of small sprat-like fish found in Indo-Pacific ocean waters. This fish as well as its relative, Spratelloides gracilis a.k.a the silver-stripe round herring or the slender sprat are both found in Vietnam and valued as food.
In Quảng Trị, a coastal province in central Vietnam, they are called cá me by local fishermen although their official Vietnamese names are cá lầm tròn or cá trích lầm. People here attract these fish by using lights at night, and then they will swim from the sea to the brackish water and got trapped in fishing nets.
One notable local cuisine dish is a fish congee made of these fish. Freshly-caught fish are added to the hot boiling congee pot with some spicy ingredients including pounded green chillis and green peppercorns.
Mix 50 g glutinous rice with 100 g non-glutinous rice, rinse. Pour in a rice cooker or a pot, then add 2 liter water then cook for 30-40 mins. If you want your congee more flavorful, you may want to roast the rice in a dry pan first.
Rinse the fish. The locals do not gut them in order to maintain the sweetness of the fish flesh. Add the fish to the boiling congee pot.
In a mortar, add chives, chillis and peppercorns then pound the ingredients. Add the spicy ingredients to the congee pot.
When the congee is almost ready, season to taste. Try 1 tablespoon fish sauce, 1/2 teaspon granule seasoning or msg. Serve the congee in a bowl topped with chopped herbs.