I don't know if you wanted to make a chocolate, vanilla, or natural (malt) flavor. Here in NYC, soda fountains used to make a chocolate malt with plain, white Carnation malted milk powder, chocolate syrup (such as Fox's U-Bet) and ice cream. No separate Chocolate flavor powder needed. Also, the amount of malt powder you add to the mix changes the 'tang'.
Besides the Horlicks that X1 mentioned, another old brand of malt powder (now also made in the USA by Nestle (also makers of Carnation)) is Ovaltine. I have seen it in a Super 1 Foods in SW Louisiana (probably Lafayette.)
Could Nestle have diddled the old formulas? Maybe. But, try upping the amount first.
post edited by David_NYC - 2009/07/21 20:03:08