The night before you are going to make the tart, put the can of coconut milk in the refrigerator. This will cause the water to separate from the cream.
When you are ready to assemble, take the can out of the fridge, open it up, and you should have a thick layer of coconut cream on the top. Use a spoon to skim that off. Save the coconut water for a smoothie later.
Put the coconut cream in a medium sized mixing bowl. It will be pretty chunky and thick at first, but just use a hand blender to slowly start mixing it. Once it has smoothed out a bit, add the maple syrup and vanilla, and keep blending for another 2 minutes, until it starts to turn into whipped cream. Set aside while you make the crust.
Before you assemble the crust, soak the dates in a bowl of hot water for 5 minutes. Once soaked, add the walnuts, almonds, dates, and coconut oil to a food processor. Pulse the mixture until it starts to come together into a thick dough-like consistency. You will have to stop the processor every few seconds to scrape down the sides with a wooden spoon. Once it has come together evenly, press the dough into a spring form pan (or a regular pie pan). *see notes
Use your hands to gently press the dough into the bottom of the pan, making sure it is an even layer.
Next, use a spatula to spread the coconut cream in an even layer on top of the crust. Lastly, arrange the peaches in an even layer on top of the coconut cream.
Put the tart in the fridge for at least 2 hours (or overnight) so that is can stiffen up a bit before you cut into it.
Notes
*I like using a spring form pan for this because you can remove the outside of the pan to make cutting the tart easier. But it still works with a regular pie pan, it will just take a little more work to cut it and get it out cleanly.