Chocolate malt is pale ale malt that's been roasted until it's a dark chocolate colour, hence the name.
It's used to add colour and roast flavour to dark beers such as porter, stout and mild.
It's best used in small quantities because it has an aggressive flavour that can overpower your beer.
Smells strongly of cold instant coffee.
The instant coffee theme comes through into the taste. It's like a mug of black coffee with one spoonful too much coffee powder.
It's less bitter than black patent malt, although still far from pleasant. There's a little sweetness present in the taste, but not a lot. Unlike with black patent malt, the bitterness (astringency) disappears fairly quickly after tasting.
Overall it's a fairly aggressive, harsh flavoured malt that should be used in small quantities.
Based on this tasting, I'd hesitate to aim for much chocolate malt flavour in a beer.
SRM Colour300 - 400
Stout, porter, dark mild, brown ale