A guide to scouting the best local food in Kenya

For her first 20 years, before coming to Nairobi, Peggy Furniss lived in the southeastern part of the country among the Kambas, Kenya's fourth-largest tribe. Because she is proud of her heritage, the traditional foods and customs of the Kambas are still very close.

This makes her an excellent guide to good food in Nairobi, for although it is easy enough to find creditable French, Italian, and Indian restaurants here, visitors who enjoy local foods are bound to be disappointed in Kenya's capital.

When I lamented this fact to Peggy, who is head of public relations at the Nairobi Hilton, she took me to the hotel's luncheon buffet and suggested that I try some irio, the one local dish among hills of sliced, roasted meats and meadows of fresh fruit and vegetable salads. Irio, Peggy explained, is a staple for many of Kenya's 70-odd tribes. It's a simple dish based on mashed potatoes, with one or more vegetables such as corn, collard greens, kidney beans, or peas mixed in.

When I tasted the irio and said I liked it, Peggy seemed genuinely surprised. She said the managements of most of the hotels and restaurants in Nairobi think travelers prefer international cuisine, especially when they are as far away from home as Africa.

''I can't speak for most travelers,'' I told her, ''but I know quite a few who would rather eat irio in Nairobi than potato salad.''

Peggy quickly became convinced of my interest in tribal cookery and made a generous offer, inviting me to dinner to taste the dishes of her tribe, the Kambas.

At her home on the outskirts of town, she took me to her backyard, where she had placed a large iron pot on three stones. This, she explained, was the traditional way of cooking muthokoi, a typical Kamba dish. It is made by boiling together dried white, large-kerneled corn with beans. The vegetables are then seasoned with salt and served with ghee.

She showed me the narrow-necked, hollowed-out calabash in which the ghee is prepared. It is filled with boiled cow's milk, left in a warm place until the milk sours, and rolled back and forth until the sour milk thickens. This butter is melted in a saucepan and the impurities are skimmed off the top, leaving the ghee.

In Kamba cookery, Peggy explained, chicken is plentiful but beef and mutton are rare. Meat is generally the garnish rather than the basis of a dish. It is first browned in ghee, then stewed with onions, tomatoes, cabbage, a little water, and salt. Occasionally green chilies are added.

That night we ate muthokoi and a delicious beef stew flavored with fresh coriander, the only herb used with any regularity in Kamba cookery.

On the way to the central market, I discovered that my driver, Jackson Keke, was a member of Kenya's second-largest tribe, the Luos. Mr. Keke told me that because they live around Lake Victoria in southwest Kenya, the Luos eat a lot of fish. Every morning around 3, the fishermen check their nets for the large, firm-fleshed tilapia and the tiny sardinelike omena.

When we arrived at the market, I saw a wide variety of glistening, fresh fish trucked in that morning from the Mombasa coast. A fine place to eat fish, I discovered later, is at the Tamarind restaurant in Nairobi.

We then went around the corner for lunch at the African Heritage restaurant, the one eating place in Nairobi that devotes its midday meal strictly to local foods.

There, we selected from a buffet table offering sukumawiki and irio plus biringanya, a dish of cubed eggplant stewed with onions and tomatoes.

Here is the Nairobi Hilton's version of irio, but bear in mind that the quantities and proportions of vegetables in this dish are left very much to the individual cook. In fact, irio is a delicious way to put leftover vegetables to good use. Hilton's Irio 6 medium potatoes, baked or boiled 3 to 4 tablespoons butter or ghee 1 cup cooked green peas or red kidney beans 1 cup cooked corn 1 1/2 cups cooked collard greens, Swiss chard, or spinach, chopped Salt to taste

While potatoes are still hot, peel and mash them with butter or ghee. Stir in remaining ingredients and place mixture into a buttered ovenproof casserole.

Heat in 350 degree F. oven until warm throughout, about 15 minutes. Serves 6 to 8. Kenya's Sukumawiki 1 pound spinach 3 tablespoons light vegetable oil 1 large green pepper, seeded and chopped 1 large onion, about 12 ounces, thinly sliced 3 tomatoes, about 1 pound, chopped 1 tablespoon chopped fresh coriander (cilantro) 1 to 2 cups diced leftover meat, optional Salt to taste

Clean spinach. Trim off roots, leaving stems intact. Set aside to drain.

Heat oil in large saucepan with cover. Add onions and green pepper and cook, uncovered, over medium-high heat until onions are soft, about 3 to 4 minutes.

Add tomatoes, coriander, meat, if used, and reserved spinach. Cover and cook over medium-high heat until spinach is cooked, stirring occasionally, about 7 minutes. Add salt to taste.

Cook, uncovered, over low flame a few more minutes, or until most of liquid has evaporated. Serves 3 to 4.