Pre heat the oven to 200°c fan, 220°c electric or Gas 7.
Put all the meatball ingredients in a blender and combine well. If you don't have a processor chop the dill and mix in a bowl by hand.
Peel the beetroot and remove the outer leaves and the base of the fennel then grate, discarding approximately a quarter of each vegetable so that you don't grate your fingers! Place in a deep ceramic ovenproof dish.
Add the oil, stock and garlic, season with salt and pepper and stir well.
Make the meatball mix into approx. 20 walnut sized balls and place on top of the veg mix.
Bake for 25 minutes.
Remove the meatballs to a warm plate, stir the sour cream into the fennel and beetroot.
Scoop the fennel and beetroot into warmed serving bowls and put the meatballs on top sprinkled with dill sprigs. You can also have extra sour cream!