Toss the thinly sliced cucumber with the salt and place in a colander. Let sit at least an hour or up to 4 hours. Spread the cucumbers out on a clean kitchen towel and blot away the excess moisture. Set aside.
Add the sour cream, chili crisp, and lemon juice to a large bowl and stir. Add the cucumber slices and toss until coated. Taste, adding more lemon or salt if needed. Store in a covered container in the fridge until ready to serve, or serve right away. Top with sesame seeds, if desired.
