Raclette, a favorite Swiss campfire dinner, comes indoors

Raclette has been favored fare for centuries among Swiss mountaineers of the Valais region, who welcome it as satisfying food quickly prepared after a long day of arduous Alpine toiling.

It derives its name from the French word ''racler'' (to scrape). To prepare raclette, the flat surface of a portion of a wheel of cheese, from which the rind has been removed, is placed near heat. As the surface of the cheese begins to curl, raclettes, or strips, of cheese are scraped from it and served on individual plates. The portion of raclettes is eaten alternately with boiled potatoes and pickled onions.

The cheese used in the Valais region for raclette is skimmed and has a rather tangy and buttery flavor, similar to the flavor of some Gruyeres. Valais restaurants serve this popular regional food, and have signs announcing when it is being featured.

Connoisseurs of raclette, however, like to eat it out-of-doors, melting the cheese over a charcoal fire. They make a game of eating it, heating the cheese over an open fire and scraping the softened cheese onto a slice of bread or a boiled potato. The combination is quickly twirled on a fork and eaten in one mouthful. If cheese drips during this interval, the ''player'' is disqualified.

Recently, while enjoying New England hospitality at Ragamont Inn, Salisbury, Conn., I was both delighted and surprised to see raclette listed on the brunch menu. I ordered it and found it to be an attractively served and appetizing offering. Served in an individual casserole, it consisted of a ring of small potatoes combined with onions and tiny gherkins - all smothered generously in a melted cheese with an agreeable tang.

Days later, I concocted my own Americanized version of raclette in a casserole. When made with the following ingredients, it serves four: Raclette Casserole 20 small potatoes, boiled and peeled 1 jar of onions, washed and drained, or equivalent of fresh small boiled onions 1 small jar gherkins 1/2 lb. Gruyere cheese, shredded 1/4 cup cream

Place potatoes, onions, and pickles in casserole. Melt cheese with cream and pour over ingredients in casserole. Place in 350-degree F. oven for about 15 minutes, or until cheese bubbles.

Slices of McIntosh or Golden Delicious apples make a fine accompaniment to this casserole on a fall day.