"The semi-blind luck of the four-day stay."

That's what my wife and I have come to call the one special discovery we seem to make on every vacation. No matter how many places we visit or how many days we stay at each one -- two days, five days, a week -- our favorite always turns out to be the place we select for its food and stay at for four days.

Our first two such discoveries, both in France, were small restaurants with rooms over the kitchen. In both cases we chose blindly from among four or five similar establishments in the same areas, each with restaurants awarded two stars by the Guide Michelin. In both cases, Bretagne in Questembert and L'Esperance in St. Pere-Sous-Vezelay, the food was better than at most of the three-star restaurants we visited.

This year we wanted to include in our vacation several days near the alpine resorts of Klosters and St. Moritz. I studied several guides and settled on a place called Tschiery's Restaurant in Davos-Laret, the only place in the area, it seemed, with both good food and private bathrooms. for luck, remembering Bretagne and L'Esperance, I made our reservation for four days.

It was wonderful. Superb food. Warm, friendly people. A lovely room. A view of alps and trees and a meadow where cows gamboled, awakening you each morning with the gentle sound of the tinkling bells they wear around their necks.

Tschiery is Tschiery Casty, a 58-year-old former ski instructor who began his training as a hotel man in the United States in 1946, returned to his native Switzerland in 1952 and got married in 1955. Two years later his wife, Elfie, left her career as a nurse to join him in the hotel business.

The two have owned several hotels since then, Tschiery always the host and manager, Elfie the chef . . . "the best woman chef in the world," her husband says proudly. He may be understating her skills.

My wife and I have eaten at 19 of the 20 three-star restaurants in France (and at more than a dozen two-star restaurants as well), and the food we ate at Tschiery's was better than all others except a half-dozen of these bastions of haute cuisine (and male dominance).

Elfie is a modest lady who, unlike most of the three-star chefs in France, does not come out of her kitchen each night to accept the plaudits of her guests. She should. She deserves them. Her warm, fresh foie gras with snow peas is marvelous. So is her consome of quail, her cassolette of lobster tails with armagnac and a half-dozen other dishes, including all her remarkably light desserts (especially the hot apple tart, various combinations of fresh fruit, homemade ice cream and fresh fruit sherbets).

Dinner at Tcshiery's can be expensive -- $40 to $50 a person (plus wine) for a full four-course dinner from the a la carte menu. But you can have an appetizer, a main course and dessert for half that, and if you stay on a semi-pension basis, you can eat a simple but good dinner from the set menu for less than $10 a person, plus wine. One night that menu consisted of fresh grape-fruit, fresh vegetable soup, filet mignon in a red wine sauce and homemade ice cream.

In the summertime the 20 rooms at Tschiery's range from about $20 to $32 per person. In the winter, when the entire area -- indeed, the entire country -- comes alive with skiers, room rates jump to $29 to $41 per person. (All prices include continental breakfast, taxes and service.)