Sendaiya's most popular natto-based meal is an 850-yen ($5.7) combo dish of rice, miso soup, one raw egg and nine kinds of all-you-can-eat natto. "Foreign customers have increased recently and now account for about 10% of all our visitors," said manager Satoshi Nagatsuka. "They come here to experience, say, something scary but typically Japanese." Most foreign customers are from China, South Korea, Thailand, the U.S. and France, Nagatsuka said. A French man who visited the shop said, "Its flavour is like cheese and is unexpectedly tasty." To attract foreign customers, Sendaiya promotes baked natto doughnuts, stressing that natto kneaded into the dough is "non-smelling." The most popular is a 170-yen plain doughnut that is mildly sweet but still has the delicate aroma of natto -- so fragile that it is often unnoticeable unless said so. "We want to win over people who have previously avoided natto because of the gooeyness and smell," Nagatsuka said.