In a food processor, combine the pitted dates, nuts, and a pinch of salt. Pulse until the mixture forms a sticky, crumbly texture.
Press the crust mixture into the bottom of a 9-inch pie pan. Use the back of a spoon to ensure an even layer. Place the crust in the freezer to firm up while you make the filling.
Place the raw cashews in a bowl and cover with water. Soak for at least 2 hours or, ideally, overnight. This softens the cashews and helps achieve a creamy texture.
In a blender, combine the soaked cashews, bananas, melted coconut oil, maple syrup, vanilla extract, and lemon juice. Blend on high until smooth and creamy. The mixture should have no lumps and should resemble a thick, creamy custard.
Remove the crust from the freezer. Pour the banana cashew filling over the crust, using a spatula to smooth the top. You can also add additional banana slices in between the layers of fill.
Place the pie in the freezer to set for at least 2 hours. This helps the pie firm up so it can be sliced.
Before serving, take the pie out of the freezer and let it sit at room temperature for about 10 minutes.
Arrange fresh banana slices on top of the pie. For a more decorative look, try layering the banana slices in a circular pattern. You can also cover the cake with vegan whipped cream.
