Place the pistachios in a food processor or pulse until small crumbs remain - almost like pistachio powder. You don't want it to turn to butter! Set the pistachio crumbs aside.
Bring the water to boil. Add the oats and the salt and cinnamon and reduce the heat to a simmer. Stir in the ground pistachios. Cook, stirring often, until the oats are thick and creamy, about 10 to 15 minutes. Turn off the heat. Stir in the vanilla extract and coconut milk. Stir in the maple syrup.
Serve the oatmeal and top with extra pistachios, flaked coconut, dark chocolate and hemp hearts.