Deep Cut Friday Wonder performed the ballad live several times, but the only studio version was released by Roberta Flack Stevie Wonder on January 35, 1974. (Credit: Evening Standard/Hulton Archive/Getty Images) Each week, SPIN digs into the catalogs of great artists and highlights songs you might not know for our Deep Cut Friday series. In January 1974, Stevie Wonder and his band performed on the German television program “Musikladen.” His set that day was heavy on songs from the 1973 masterpiece Innervisions , and closed with a rendition of the 1972 hit “Superstition” that I saw many times on VH1 growing up. The “Musikladen” appearance also included two previously unreleased new songs. The instrumental “Contusion” would eventually come out on 1976’s Songs in the Key of Life .…