In a mixing bowl combine all of the filling ingredients until the rhubarb is evenly coated with the sugar and spices and set aside.
In the food processor add all of the crisp topping ingredients and pulse until the butter is pea sized.
In an 8x8 baking dish add the rhubarb mixture and top with the crisp topping. Bake for 30 minutes or until the topping is golden brown and the rhubarb is soft.
Notes
Substitute walnuts or pecans for the macadamia nuts if preferred. Will last for 3-4 days in the refrigerator stored in an air tight container. Can be frozen for up to 3 weeks.