Hors d'oeuvres and dessert, delightful but barely filling, were the fare at Frederica von Stade's Kennedy Center recital Saturday night. Curiously, the engaging mezzo soprano appeared to be in the best of form, showing no need for such a light diet. Apart from an occasional harsh quality in the lower register, her voice sounded agile and strong, with a control, particularly in the softer passages, that proved a special joy.

The starting course was a group of Italian baroque songs that drew rich tones and finely shaded lines from Von Stade. In one of the evening's rare moments of depth, she transformed Scarlatti's "Se tu della mia morte" into a touching portrait of suffering love. Marcello's brilliant "Il mio bel foco" brought the set to a dazzling finish.

Mahler's Four Songs from the Ruckert Lieder probably were meant to be the main course. Though Von Stade evoked some lovely moments, she did not find the sustained intensity needed for real substance. Dessert began with Rossini's "Tanti affetti," whose spectacular coloratura passages Von Stade molded with shimmering delicacy.

The sweets continued after intermission with a set of French songs that poured forth from Von Stade like a sparkling white wine. A closing set of American songs offered little in the way of nutrition, and the last -- Roger Nelson's "Jimmy Jet and His TV Set" -- was pure junk food, a slight way, indeed, to end the program.

With an exquisitely refined touch, accompanist Martin Katz subtly extended Von Stade's interpretative aims. In the closing piano phrase of the last Mahler song, he, in fact, reached the transcendent level that eluded the singer.