Cao Bong Thi, 73, marked the annual Moon Festival earlier this month just as she would have in her native Vietnam - by eating her favorite foods in the company of family and friends.

After days spent shopping and chopping, Bong made 125 egg rolls and enough servings of bun sau, a stir-fried vegetable dish served over steamed rice noodles, to feed all the 100 people celebrating at the Nationalities Senior Center at 11th and Rockland Streets in Logan.

Usually, 50 or more men and women - refugees and immigrants from Southeast Asia in their late 70s and early 80s - attend programs and eat lunch at this senior center, which rents space in the basement of a Presbyterian church.

On most days, the elders practice tai chi and chair yoga here. They play bingo and hear speakers in their native languages on topics such as elder law and prostate cancer. English classes are a fixture in the center's class schedule. And every brochure, flier, and announcement is in Mandarin Chinese, Cambodian, and English.

The seniors themselves planned this special Moon Festival, said Tara Swartzendruber Landis, the center director. It is a holiday traditionally celebrated with songs, dance, and a store-bought sweet called mooncake.

Compared to other Asian treats, mooncake is not particularly easy to make. It is an acquired taste, and the cakes are relatively expensive ($4 or more per piece).

It's been compared in popularity and flavor to Christmas fruitcake. But eating mooncake at this time of year is a tradition, and few ethnic groups are known to break easily with tradition.

So, the senior center's event featured singing to tunes from a seven-language karaoke machine, playing games of Chinese chess and dominoes, dancing to the electric slide and the chicken dance, and eating lots and lots of good food.

"When we have an event like this, people will cook for days, and whole families get involved," said Landis.

Shang Huiyan, who is in her mid-80s and grew up in China, served pots of green tea while the elders nibbled on fried dumplings, crispy beans, preserved watermelon seeds, and candied cashews (see recipe).

Bong's bun sau (see recipe), calls for dried lotus, the root of the water-lily plant. Many U.S.-born cooks may not have experience with it, but it's worth learning about as a cooking ingredient. (See accompanying story.)

The festival menu also featured fresh (not fried) Vietnamese spring rolls made by Pham Gerhardt, 74. (See recipe.) After all the ingredients for the rolls are prepared, assembling the rolls is a fun group experience that children might especially enjoy.

The rolls are served with a peanut dipping sauce (see recipe) that can be made more or less spicy by varying the amount of chili paste added. The sauce can be made in advance and refrigerated.

When the dessert - the pretty, store-bought mooncakes - was served, most of the seniors took theirs home, "for later."

As is the case with so many home cooks expecting company, the women preparing the main dishes cooked in quantities that outpaced the appetites of the assemblage.

Landis wasn't surprised. It happens all the time, she said.

"You never leave here hungry."

Cooking With Lotus Root

From the outside, fresh lotus root seems like nothing special. But peel away the inedible outer skin and cut away the ends, and you find a creamy-white flesh with lacy holes that run from end to end like small tunnels.

Inner beauty is not this Asian root vegetable's only attraction. It can be added raw to salads, stir-fried, or simmered in stews.