Half one pound of cucumbers lengthwise (hot dog style).
In a large stock pot, place the halved cucumbers, onion, garlic, dill sprigs, turmeric, red pepper flakes, 1/2 teaspoon of salt and water and bring to a boil over high heat. Reduce heat to low and simmer for about 45 minutes to 1 hour.
Once the broth is reduced and concentrated in flavor, strain the cucumber broth into a sealable container. Stir in the vinegar and cover. Place into the fridge to chill, at least 8 hours.
One hour before serving, dice the additional one pound of cucumbers. Place the cucumbers into a bowl and top with 1/2 teaspoon of salt. Stir to coat and chill in the fridge for one hour.
Place a kitchen towel on a cutting board. With a slotted spoon, remove the cucumbers from the fridge and place in one layer on the towel. Pat the cucumbers dry.
Add the desired amount of cucumbers into cold serving bowls. Place any remaining cucumbers back into the fridge to be used at a later time (they will remain crunchy for a day or two if properly salted and patted dry). Pour the cold cucumber broth over the cucumbers. Top each bowl with a dollop of yogurt and fresh dill and mint. Serve immediately, salt to taste.