Cut the root and stem ends from the beetroots and cut each beetroot into 4 pieces. Place the beetroot onto a perforated tray above a solid tray and into a pre-heated oven steam setting 100 °C for 1 hour.
Peel and roughly chop the garlic and add it to the bowl/jug of a blender along with water, lemon juice, tahini and ground cumin. Blend on high speed until thick and smooth.
Once the beetroot had steamed use some paper towel to drain the beetroot and also peel away the skin. Place the peeled beetroot into the blender with the other ingredients and blend until smooth. Check and adjust seasoning with salt and if required lemon juice.
To finish spoon some beetroot hummus onto a plate and sprinkle over some sumac, picked coriander leaves and a drizzle of extra virgin olive oil and serve.