1. Whisk together the fish sauce, lime juice, maple syrup, garlic, chile pepper, and optional sesame oil.
2. In a larger bowl, mix the tomatoes and cucumbers together. Add the dressing and mix again. Taste and adjust the amount of fish sauce and/or maple syrup, if necessary.
3. Spoon the salad onto plate(s) and garnish with raw cashews, if you like.