  A mixture of ground nuts -- such as hazelnut and almonds -- sugar and liquid (egg whites and perhaps a liqueur), nut pastes are frequently added to baked cakes, tarts and pastries for added richness and flavor. Although prepared almond and hazelnut pastes (and marzipan, a sweetened almond paste) can be found at many gourmet markets and specialty stores, they can easily be made at home. Continue reading below for recipes for homemade pastes, including the hazelnut paste we used when adapting Valerie Confections' hazelnut-orange tea cakes , pictured at left, for our Culinary SOS column (they take a little time, but these amazing little cakes are well worth the effort!  