I bought a "Juice" book recently while away on holiday, but haven't tried any recipes yet. Here are a couple of beetroot combinations you could try though:
Fruity Beety Beauty - 2 beetroots (small) trimmed and washed, 1 large orange (peeled) and small handful of fresh raspberries.
Carrot, Beetroot and Ginger Juice - 2 large carrots, 1cm piece of peeled ginger root and 1 small beetroot washed and trimmed.
To make them in the TMX I would add the above ingredients (chopped up a bit) with a handful of ice and blend on speed 8 for 30 seconds. I would then add about 500g of water and blend for 30 seconds on speed 8 and then another 30 seconds on speed 10.
I hope this helps.
