Peel the carrots and beetroots, then shred or grate roughly.
Squeeze the water out of the grated vegetables and wrap them in paper kitchen towel.
In a mixing bowl, beat the eggs lightly then add the grated vegetables, garlic, flour and dill.
Grind the cumin in a mortar, add to the mixture. Season with salt & pepper and combine well.
Make the sauce: dry-fry the walnuts then chop them up roughly and mix with the yogurt and onion. Set aside.
Heat the oil in a frying pan then, using a teaspoon, add dollops of your carrot & beet mixture to the pan. Pat down the top of each fritter with the bottom of the spoon. After a minute or so flip the fritters and cook until golden brown and crispy.
Transfer them onto kitchen paper to soak up the oil. Make the next batch.
Arrange the fritters on a large serving dish, spoon a small blob of sauce on each then top with a piece of walnut and sprinkle with dill. Serve at room temperature.