Make the soup: Put the English cucumber slices in a blender and add 1/4 cup cold water. Blend on low speed until smooth (you don't want to whip too much air into the soup). You may have to stop the blender to push the cucumbers down toward the blade. Season with salt, pepper and a touch of honey, if a little sweetness is needed. Transfer to a small bowl, then set it in a larger bowl filled with ice water to chill, about 3 hours.
Meanwhile, make the sauce: Combine the chile pepper, honey, paprika and cumin in a small bowl and mash well with the back of a spoon so the ingredients meld. (If you own a mortar and pestle, this is a great chance to pull it out.) Stir in the yogurt and vinegar. Season with salt.
Just before serving, drizzle the Kirby cucumber spears with the lemon juice and season with salt and pepper. Give the soup a final stir and pour into small glasses. Drizzle the yogurt sauce on top, garnish with the cucumber spears and serve immediately.