Preheat the oven to 200 degrees Celsius (390 degrees Fahrenheit)
Wash the beets and place in the spiralizer and cut into thin noodles or julienne. Place the beet noodles onto a baking tray, drizzle with 1tbsp olive oil and bake in the oven for 6-8 minutes or until they become soft. Remove from the oven and allow to cool.
In a bowl combine the watercress, walnuts and beet noodles. Add the orange right before serving to prevent the colour from the beets bleeding onto the oranges.
Toss with raspberry vinegar, olive oil and salt and pepper and serve.