Slice the cucumbers into thin 1/8-inch rounds using a sharp knife for clean cuts. Toss the slices with half of the sea salt in a colander and let them sit for 15 minutes. Afterward, press the cucumber slices gently with paper towels to remove excess moisture.

In a large mixing bowl, whisk together fresh lemon juice, extra virgin olive oil, freshly grated lemon zest, and a pinch of red pepper flakes until emulsified.

Add the cucumber slices to the dressing in the bowl and toss to coat evenly.

Add remaining sea salt and black pepper. Tear fresh basil leaves and add them to the bowl, tossing gently.

Transfer the salad to the refrigerator and let it chill for at least 2 hours before serving.