Preheat oven to 180°C fan-forced. Line a baking tray with non-stick baking paper.
In a large bowl, combine the sugar, maple syrup, vanilla bean paste and water. Add the rhubarb and mix well to coat. Transfer to the lined baking tray and bake in the oven for 10 minutes or until just tender, ensuring the rhubarb doesn’t collapse. Set aside to cool.
Meanwhile, in a large saucepan combine the quinoa and the water and bring to the boil.
Reduce the heat to low and cook, covered for 15 minutes or until the quinoa is tender and the water is absorbed. Add the macadamia milk and cook, stirring, for a further 5 minutes or until the quinoa boils and thickens.
To serve, divide the quinoa porridge between bowls and top with the baked rhubarb, pouring over the juices. Sprinkle with the macadamias and serve with extra macadamia milk.