Peel the cucumbers using a vegetable peeler or sharp knife, then thinly slice them into rounds, aiming for paper-thin slices that are evenly cooked through.
Place the cucumber slices in a large bowl, spreading them out to make a single layer if possible.
Pour the hot vinegar over the cucumber slices, watching as they sizzle and release a sharp aroma. Gently toss everything together to coat each slice evenly.
Add the minced garlic, salt, sugar, and chopped dill to the bowl, then toss again to distribute the seasonings and herbs throughout the cucumbers.
Sprinkle chili flakes over the mixture if you like a bit of heat, then give everything one last gentle toss.
Let the salad sit at room temperature for at least 10 minutes, allowing the cucumbers to soak up the tangy vinegar and develop a crisp yet tender texture.
Give the salad a final toss before serving, adjusting seasoning if needed, and enjoy the bright, crunchy, and tangy flavors straight from the bowl.