Shred the Green Papaya: Use a mandoline, julienne shredder, or chef's knife to shred the green papaya into crunchy lengths. Once shredded, place in a bowl of cold water to preserve its crunchiness. Drain well before using in the salad.
Roast the Peanuts: Pour a single layer of raw peanuts into a dry pan and heat over medium heat until they are roasted (approximately 30 minutes). Allow the peanuts to cool, then remove their skins.
Prepare the Vegetables: Peel the garlic. If it's a large clove, feel free to use a smaller portion of it. Cut the long beans into 2 inch lengths. Slice the cherry tomatoes in half.
Mix the Dressing: Mix the lime juice and palm sugar together, stirring until the palm sugar is completely dissolved. If you are starting with hardened palm sugar, you can help it dissolve by slicing it finely or microwaving it with a drop of water for several seconds.
Shred the Dried Shrimp: If you like, you can pulse the dried shrimp in a blender until they form a fine powder. Otherwise, feel free to skip this step and add the dried shrimp whole.
Pound Everything Together:
Add the roasted peanuts to the mortar and pestle and pound until they are broken into quarters. Take out and set aside.
Pound the garlic until its completely broken down. Then add the Thai chilis and pound as much as you like (the more you pound, the spicier the salad will be).
Add the long beans and tomato halves and pound until just bruised. The tomato juice should be released, but the tomato itself should still be intact.
Add the shredded papaya and pound to mix with the other ingredients. Use a spoon as needed to help mix.
Add the shredded dried shrimp, lime juice / palm sugar mixture, and fish sauce. Taste and adjust the seasonings.
Scoop onto a plate and sprinkle with the chopped roasted peanuts. Serve and enjoy immediately.