Prepare the Cucumber Base: Set a fine-mesh sieve over a medium bowl. Using the large holes of a box grater, grate the unpeeled English cucumber directly into the sieve. Sprinkle with a generous pinch of kosher salt and toss gently to combine. Allow the cucumber to drain for at least 10 minutes to release its excess water.
Press and Dehydrate: After draining, use the back of a spatula or your hands to press the grated cucumber firmly against the sieve, expelling as much liquid as possible. Discard the pressed cucumber water. Transfer the dry cucumber shreds to a separate, larger mixing bowl.
Bloom the Chia Seeds: In a small bowl, combine the fresh lemon juice and the white chia seeds. Stir and set aside for 5 minutes. This step allows the chia seeds to begin gelling, which will add thickness and a boost of fiber to the final dip.
Construct the Yogurt Foundation: To the bowl with the dry cucumber, add the non-fat Greek yogurt, extra virgin olive oil, minced garlic paste, lemon zest, and the remaining 1/4 teaspoon of kosher salt.
Incorporate the Flavor Elements: Pour the bloomed chia seed and lemon juice mixture into the yogurt base. Add the finely chopped fresh dill and mint.
Combine and Chill: Using a spatula, fold all the ingredients together until they are thoroughly combined and the dip is uniform in consistency. For the best flavor, cover the bowl and chill in the refrigerator for at least 30 minutes to allow the flavors to meld. Serve cool.