Praline paste by John Spottiswood.

This paste is made with almond or hazelnut butter and sugar, and it's used to make candy and other desserts. It's hard to make yourself, since homemade nut butters tend to be gritty. Unfortunately, it's also hard to find commercially prepared praline paste, though you can order it online at www.kingarthurflour.com. The oil sometimes separates and rises to the top, so stir before using.