1 (1/4-inch-thick) slice galangal, finely chopped (optional)
2 tablespoons nam pla (Thai fish sauce), divided
¼ cup fresh lime juice, divided
½ cup water or no-sodium chicken broth
Red pepper flakes, to taste
½ cup thinly sliced culantro leaves or roughly chopped cilantro leaves and stems
½ cup loosely packed fresh mint leaves, plus more for garnish
16 green beans, trimmed, for serving (optional)
4 thin (1/2-inch-thick) wedges green cabbage, for serving (optional)
4 cups cooked Thai sticky rice or jasmine rice, for serving (optional)
Toast rice in a medium skillet over medium-low heat and cook until medium brown and aromatic, about 3 minutes. Stir rice every 30 seconds to ensure it browns evenly. Immediately transfer rice to a heatproof bowl to cool completely before grinding in a mortar or a spice grinder to a coarse powder. Set aside.
Toast galangal in a large skillet over medium-high heat until dry to the touch and fragrant, about 1 minute. Transfer to a large bowl.
Add shallots, 1 1/2 tablespoons of the fish sauce, and 2 tablespoons of the lime juice to bowl with galangal; stir to mix.
In the same skillet over medium heat, add pork and water and cook, breaking meat with the blunt end of a spatula into tiny pieces, until no pink remains, about 6 minutes. Transfer cooked pork and juices to the bowl with dressing.
Add 2 teaspoons of the reserved toasted rice powder and toss everything together while the meat is still warm. Taste to check if you need the remaining fish sauce and lime juice; salad should be sour first, then salty. Correct seasonings as needed, then add red pepper flakes to taste.
Stir in culantro and mint leaves. Transfer salad to a serving platter and, if using, arrange cabbage wedges and green beans alongside. Sprinkle the remaining 1 teaspoon of toasted rice powder over salad and garnish with more mint leaves, if desired. Serve warm with rice.