If using raw beets, grate them and let sit with a pinch of salt for 10 minutes.
Blend beets, yogurt, water, lemon juice, and garlic until smooth.
Transfer to a bowl and stir in cucumber, dill, and chives.
Season with salt and pepper.
Chill for at least 2 hours before serving.
Garnish with extra yogurt, herbs, and sliced eggs if desired.