Tonka beans have an intense vanilla-almond flavor with hints of cherry and hay. They're grated fresh like nutmeg and used sparingly - typically 1/8 teaspoon per recipe serves 6-8. Tonka beans contain coumarin and are banned for consumption in the US, so substitute with vanilla extract (use 3-4 times the amount) or vanilla bean paste. In Europe and other regions where available, tonka beans add sophisticated flavor to mousses, custards, and buttercreams.