I was in the area and noticed a new Chinese restaurant that I believe opened just this year. It replaces a fast-food place which had replaced a Cajun shrimp place. The English name is "Shanghai Dumpling House". The Chinese name is Nanxiang Xiaolong, which may be reference to a XLB's alleged birthplace in Nanxiang, China (sorry folks, my knowledge of Mandarin and written Chinese are both limited). The staff there spoke English just fine, but just for fun, I tried to muddle my way through the meal with Mandarin.
I was eating by myself, so I ordered the juicy pork dumpling (aka xiaolongbao or 小笼包) and their beef rolls pie (牛肉卷餅). Eight XLB cost $5.95. The beef roll cost $5.55
It took a while to get the XLB. The waiter said that they make it fresh, so they made it after I ordered it. It was pretty good. There was a lot of soup. The flavor was more on the subtle side--the pork filling was very fresh, and I could taste it very clearly. For reference, the aroma and flavor weren't as sharp as those from Dean Sin World. The skin was moderately thin and stretched enough to avoid breaking as I lifted them off the steamer.
I didn't like the beef roll that much. The roll itself had a nice, crispy exterior, but they used too much hoisin sauce--it overwhelmed the dish. 101 Noodle Express' version may cost more, but you get more than double the amount, and it tastes better.
Monrovia is not known for its large Chinese population. I'm surprised that you can get some real Shanghai dishes here, including tripe, intestines, etc. They also have a small number of dishes designed for the non-adventurous eater: sweet and sour chicken, broccoli beef, and crab rangoon.
It's too early for me to pass judgment on this place because I've only had two dishes there. For those who live near Monrovia/Duarte, it is certainly more convenient than driving to San Gabriel, Monterey Park, or Arcadia.
Shanghai Dumpling House
215 E. Foothill Blvd., Monrovia