Cook the beetroot: place them in a pan and cover with cold water. Bring to boil and boil for 50 minutes, until soft and when you try to peel the skin away with a blunt knife, the skin comes away.
Drain and cool.
Whilst the beetroot is cooking, make the walnuts:
Preheat the oven to 170˚C/340˚F.
Whisk the honey with the orange juice and smoked paprika, then stir in the walnuts and mix until the walnuts are coated. Pour onto a baking dish lined with baking parchment and bake for 10-15 minutes until golden, stirring halfway. Cool on the dish.
For the dressing, mix the olive oil, red wine vinegar and orange juice together and season - remembering the feta is salty.
Peel the cooled beetroot and slice, then arrange on a plate with the spinach, walnuts and feta (once you mix the feta will become beetroot coloured so it’s best to not stir.)