Pulse all the nuts in a food processor or a high-powered blender until finely chopped. Add the dates, cinnamon, lemon zest, and salt, and process until well combined, and sticks together. If the mixture seems too wet, add more ground nuts.
Transfer the dough to a 10-12” tart pan, and press firmly into an even layer on the bottom of the pan and up the sides. Place in the freezer for 2 hours, or refrigerate overnight.
Arrange the sliced peaches in concentric circles in the crust. Sprinkle with lemon juice. Slice, and serve.