The eighth recipe I made from the Savory Tarts & Pies section (the 52nd recipe overall in this book) of The Modern Baker by Nick Malgieri, was the one for Gruyere, Scallion, & Walnut Tart, on page 141. (We are not publishing recipes from the book, so if you like what you see, buy the book and bake along with or without us).
I was a little skeptical about the nuts in this, but they work wonderfully well and do not loose their crunchy texture, even after a couple of days in the frig and being warmed up in the microwave at school for lunch. I made a full-size (11") tart and we had leftovers which Mark and I both took to work for lunches. He said it warmed up very nicely in the microwave and was not soggy, etc. and I found that as well. Definitely a repeat, the combination of flavors is wonderful.