I have this book and can highly recommend it: http://www.amazon.com/Kaffeehaus-Exquisite-Desserts-Classic-Budapest/dp/0609604538/ref=sr_1_4?s=books&ie=UTF8&qid=1432777379&sr=1-4&keywords=austrian+pastries+and+desserts
Hungarian Walnut Torte with Walnut and Espresso-Custard Buttercream adapted slightly because I like coffee with my walnuts.
http://www.amazon.com/Kaffeehaus-Exquisite-Desserts-Classic-Budapest/dp/0609604538