When Rosa Gomez, of Bethesda, becomes nostalgic for Argentina she shops at Las Americas for mate' tea and brews the hot tea that she remembers drinking from a hollow gourd with her father's farm workers. Gomez also buys dulce de leche, a spreadable caramel paste that she serves with custard, and dulce de batata, a jellied sweet potato eaten with hard cheese. These foods, Gomez says, are a remedy for her occasional homesickness.

Las Americas, a store catering to Washington's Latin community, sits in Ritchie Center tucked between other ethnic stores selling Indian and Japanese food and Persian sweets. The small shopping center is located just off Rockville Pike where car dealers and fast food predominate, but Eric Espada, the shop's 25-year-old owner, knew it was a good location when he opened the first of his two locations (the other is in Silver Spring).

"Contrary to what most people think, there are no boundaries to the Hispanic community. Adams Morgan and Takoma Park aren't the only neighborhoods. My customers live in McLean, Potomac, Gaithersburg and Bethesda, and there's a large Hispanic community in Rockville," explained Espada.

Espada controls the store's activity from a front counter where the cash register sits. A television, tuned to a Spanish station, hums in the background while Espada chats with shoppers as they unload baskets filled with yuca, frozen papaya, chayote and nance. Espada, whose father is Bolivian, grew up on Bolivian food, so he understands his customers' preference for homeland delicacies.

When the phone rings, Espada switches easily from English to Spanish to talk with the diplomats, military attache's and World Bank employes who order ethnic specialties prepared by Alberto Silva, the shop's ebullient cook.

Silva immigrated from Argentina where he worked as an electronics technician. Now he makes a living from his favorite hobby -- cooking -- and he's proud of the knowledge he's acquired about various countries' culinary nuances. It's a matter of spices, he says. He can make either Salvadoran or Argentine sausage (Argentine has no onion), or roast a pig Cuban or Argentine style. He uses blue fish, squid, oysters and clams in his seviche and always has a Peruvian ham simmering in a secret sauce.

He offers a visitor a taste of chimmichurri, a forceful Argentine sauce of garlic, spices, chiles, onions, olive oil and vinegar, and gains an admirer. Then he makes a Peruvian ham sandwich with red onions and hot peppers called a butifarra. He'll make empanadas filled with corn, chicken or vegetables to order.

An Ecuadorian, now living in Wheaton, buys chunks of marinated beef heart and barbecues the skewered hearts over high flames. He said that he serves the hearts, called anticucho, with corn and potatoes to contrast with the spicy meat.

A woman from Colombia buys short ribs to make soup. Brazilians shop for palm oil, farinha de mandioca and farinha de milho. There are bananas for baking, eating and frying and black clams from El Salvador that Silva suggests eating with chopped onion, lemon and hot pepper. Dried potatoes and tropical juices sit on shelves and cream and cheese from El Salvador chill in the refrigerator. Espada said that if three people ask for something that he doesn't stock, he'll try to get it from his distributors.

Espada said that he was surprised to find that some customers try to bargain with him.

"At first I thought it was because of my prices, but then I realized that the enjoy this kind of interchange. It's part of shopping, and they're used to bargaining in South American markets," said Espada, who has noticed other shopping patterns too.

"Some people come in twice a week, people used to American food come in once a month, and newcomers to America will drive a long way just for soap powder, because they feel more secure speaking Spanish and more comfortable here than in Giant."

Espada's father, Humberto, also enjoys dropping in whenever he can. He smiled when he learned that his son calls him the store's social director.

"I like talking to other Latinos," explained Humberto Espada. "I'm learning new Spanish expressions and different names of food. And even though we all speak Spanish, I'm now able to tell which country people come from by the way they speak the language."

He recalls taking his son shopping for Bolivian food at an ethnic store in Silver Spring, but he never dreamed that Eric would own a similar business. He was sure, though, that Eric, who ran a gourmet meat company while studing marketing and international business at American University, would do something original.

"I think that Eric's Bolivian connection gave him the confidence to run a store like Las Americas," said his father.

Eric agrees, and pauses to sell one of his aunt's homemade saltenåas to a sublimely happy woman who had just discovered the shop.

"I kind of fell into this business. When I got out of school I was looking for a job where I could be my own boss; I knew that I didn't want to work for anyone else," said Eric. "Now I've discovered that I like shopping for fresh produce early in the morning, and I don't even mind the 80-hour work week. I'm also pleased that I'm doing something for the Hispanic community, and everyone seems glad that I'm in business."

Las Americas, 785 E. Ritchie Center, Rockville Pike, 424-9550. Hours: Monday-Saturday, 10 a.m.-8 p.m.; Sunday, 10 a.m.-9 p.m.

Las Americas, 8651 16th St., Silver Spring, 588-0882. Hours: Monday-Friday, 11 a.m.-9 p.m.; Saturday, 10 a.m.-8 p.m.; Sunday, 10 a.m.-4 p.m.