To prepare the dressing, add the sugar and warm water in a bowl. Mix together until the sugar has fully dissolved. Add lime juice, fish sauce, minced garlic, and chopped thai chili peppers. Mix well until combined. Adjust the sweetness and saltiness to taste. Place the dressing in the fridge while you prepare the salad.
Wash the tomatoes and pat dry. Cut the tomatoes in half and remove the core. Cut each half into 4 pieces.
In a bowl, combine the tomatoes, sliced shallots, sliced onions, and chopped cilantro.
Pour the dressing over the tomatoes and mix to coat well. Allow this to sit for 10 minutes before serving to allow the flavors to develop.
Course: Appetizer, Dinner, Lunch, Salad, Side Dish, Snack