To prepare the cucumbers, after washing the cucumbers, trim the ends, then use the flat side of a knife to gently smash them until they crack open. Cut into bite-sized pieces, place them on a plate, and toss with the sugar. Let rest for 5 minutes, then discard the released liquid.
To make the dressing, in a bowl, combine the sesame seeds, garlic, shallot, red finger hot pepper, and chili flakes.
To bloom the aromatics, in a small pan over high heat, heat the cooking oil until hot and just starting to smoke, then carefully pour the hot oil over the aromatics. Add the Chinkiang vinegar and soy sauce, then mix well.
To assemble, pour the dressing over the cucumbers, then add the toasted peanuts and cilantro and gently toss until evenly coated. Serve immediately.