THE SWISS MAY claim it as their own, but muesli is a dish as American as salad bars.

A large crockery bowl of plain rolled oats, after all, sounds no more exciting for a company breakfast than a platter of iceberg lettuce would at dinner. But it's the "fixings" -- row upon row of fruits, nuts and grains to mix and match -- that turn this grain-based breakfast or brunch into a festive buffet that is refreshingly nourishing and chewy in the midst of seasonal sweets.

The dish was originated by Max Bircher-Benner -- a Swiss doctor who believed, much as our own John Kellogg at the turn of the century, that the Swiss diet was too rich and fat-laden, and convinced the Swiss to incorporate this concoction into their diets. It began as uncooked rolled oats, chopped apples and yogurt. Now it typically has raisins -- a sort of granola au naturel that only gets better with the addition of more grains, nuts and fruits.

And in some settings it has grown to an entire buffet. A treat to Swiss palates weary of gray bratwursts and boiled white potatoes, it is no less the perfect choice for holiday brunch -- a sideboard full of muesli makings beginning with a large bowl of plain rolled oats and a side dish of natural unflavored yogurt that replace the usual Christmas season syllabub and plum pudding.

Guests begin with large earthenware "soup-plates" -- broad plates with shallow rims -- to contain the cereal. Next are the oats, yogurt, a crock of honey, granulated brown sugar and cream. Bowls of complementary ingredients, three rows deep, are labeled as to their contents.

The row of additional grains starts with rye and barley and moves to whole oats (in kernels as opposed to "rolled") and soaked wheat (bulgur). Separate bowls are filled with seeds -- sesame, for instance.

Another row offers fresh fruits in season: perhaps plums and chopped peaches, but these days probably the original chopped apples and pears (tossed with lemon juice). Bowls of dried fruit contain currants, raisins, chopped dates and chopped prunes. A row of nutty additions include hulled pumpkin seeds, hazelnuts, almonds, cashews and walnuts.

That's the ultimate muesli service in Switzerland, as presented at the White Horse Hotel in Wolfgang, a resort town comparable to Gatlinburg, Tenn. It is surrounded by gorgeous mountains, reflected in a beautiful lake, and full of little shops that sell "Welcome to Wolfgang" ashtrays. At the White Horse, though, the muesli is only a start. Yawning wicker baskets lined with great cloths and filled with wonderful breads form a backdrop for the buffet table. Twisted white rolls, whole-wheat rolls with caraway, slices from an egg loaf, poppy seed rolls, the dense whole-wheat bread ubiquitous at European breakfast tables and a dark, heavy loaf full of dried pears, currants and other dried fruit but not as sweet as fruitcake (perhaps the perfect holiday compromise). The buffet also holds small wicker baskets lined with napkins for patrons to load with bread choices and carry back to their tables.

With the breads are offered cheeses -- mostly strong, nosey ones -- with sausage and selections of jams and preserves. A large bowl holds a whipped fresh cheese -- a somewhat grainy, yet smooth, tart cheese -- a spoonable cheese, reminiscent of a cross between farmers' and cream cheeses yet resembling whipped cream sitting in its bowl.. MUESLI BUFFET (12 servings or more) 6 to 8 cups rolled oats 3 to 4 cups plain yogurt Honey Brown sugar Grains (serve 3 or more of the following) 1 1/2 cups whole rye 1 1/2 cups whole oats 1 1/2 cups bulgur (soaked in equal part boiling water) 1 1/2 cups buckwheat (also called kasha, lightly toasted) 1 1/2 cups rolled barley 1 1/2 cups wheat germ Seeds (serve 2 or more of the following) 1 cup hulled sunflower seeds 1 cup hulled pumpkin seeds 1/2 cup toasted sesame seeds Fruit (serve 4 or more of the following) 2 cups fresh fruit in season (winter -- pears, apples, peeled and seeded, sectioned oranges) 1 cup chopped dried dates 1 cup chopped dried figs 1 1/2 cups chopped dried pears 1 1/2 cups chopped dried apricots or peaches 1 1/2 cups chopped dried apples 1 1/2 cups chopped prunes 1 1/2 cups golden or sultana raisins 1 1/2 cups currants 1 cup flaked coconut Nuts (serve 2 or more of the following) 1 cup raw cashews, toasted 1 1/2 cups chopped walnuts 1 1/2 cups chopped almonds, toasted 1 1/2 cups chopped hazelnuts, toasted

Place each item in separate bowls with soup spoon (use serving spoons for the oatmeal and yogurt and a teaspoon for the toasted sesame seeds). Serve with attendant breads, sweet butter, jams, sausages and cheeses, if desired. Dense hot coffee should be served with generous portions of milk along with spice teas and freshly squeezed orange juice.