In a mortar and pestle, pound 2 cloves of garlic and 2 Thai bird's eye chilies together.
Add lime juice (juice of 2 limes), 2 tablespoons fish sauce or soy sauce, and 2 tablespoons palm sugar or brown sugar to taste.
Toss the cucumber slices (2 cucumbers) and halved cherry tomatoes (1 cup) in the dressing until well combined.