Step 1: Wash the cucumbers thoroughly. Place them one at a time on a sturdy cutting board. Using the flat side of a large chef's knife or a rolling pin, firmly 'smack' each cucumber several times until it cracks and begins to split open along its length.
Step 2: Once smacked, roughly chop the cucumbers into irregular, bite-sized pieces (about 1-inch chunks). The jagged edges help them absorb the dressing better.
Step 3: Place the chopped cucumbers in a colander. Sprinkle with 1/2 teaspoon of salt and toss to coat. Let them sit for 10-15 minutes to draw out excess water. Gently press them down with a spoon to release more liquid, then pat them very dry with paper towels.
Step 4: While the cucumbers are draining, prepare the dressing. In a small bowl, combine the minced garlic, rice vinegar, soy sauce, sesame oil, sugar, and chili flakes. Whisk until the sugar is dissolved and all ingredients are well combined. If using, add the Sichuan peppercorn oil.
Step 5: Transfer the dried cucumbers to a medium mixing bowl. Pour the prepared dressing over the cucumbers. Toss thoroughly to ensure every piece is coated.
Step 6: For best results, cover and refrigerate the Smacked Cucumber Salad for at least 15-30 minutes to allow the flavors to meld and the cucumbers to chill. Taste and adjust seasoning if necessary before serving.
Step 7: Serve chilled, garnished with toasted sesame seeds, fresh cilantro, or chopped green onions, if desired.