Put the turnip in a small saucepan and cover with water. Bring to a boil then simmer until tender, about 10 minutes.
Put the turnip with 2 - 3 tablespoons cooking liquid in a food processor. Add the rest of the hummus ingredients and process until smooth. If the mixture is too stiff add 1- 2 tablespoons water. Taste and correct seasoning.
To serve: put the hummus in a dip plate, spread it with a spatula or big spoon. Drizzle olive oil, add the toppings and garnish. You can eat this with pita bread, crackers, nachos and even croutons.
To make the croutons: dice a few slices of stale bread. Put on a baking tray, drizzle with olive oil, sprinkle some salt and bake at 400F/200C for 10 - 15 minutes.