Using a cheese grater, grate beets into a large bowl. Add chopped cucumber (chop into very small pieces), green onions, and chopped dill frons to the bowl. Season with Kosher salt and a pinch of ground black pepper.
Pour buttermilk over veggies and gently stir to combine. If mixture doesn't seem like a soup consistency, add more buttermilk to taste. Place bowl in the fridge so soup can chill and flavors can meld for at least 30 minutes. Soup may be stored in the fridge for up to 5 days, and the flavor just gets better!
Recipe by Eating Made Easy at https://eating-made-easy.com/hot-pink-buttermilk-beet-soup/