Ingredients

• 12 small green Thai chiles, stems removed
• 2 lemongrass stalks, bottom third only, tough outer layers removed, smashed with the back of a knife, thinly sliced
• 2 shallots, coarsely chopped
• 8 small or 6 large garlic cloves
• 1 (4") piece galangal, peeled, thinly sliced
• Zest of 1 makrut (Thai) lime (optional)
• 1 cup Thai basil leaves
• 1 Tbsp. chopped fingerroot (kra chai) in brine (optional)
• 2½ tsp. shrimp paste

Instructions

1. Blend chiles, lemongrass, shallots, garlic, galangal, makrut lime zest, basil, fingerroot (if using), shrimp paste, and ½ cup water in a blender on high speed, scraping down sides and adding more water if needed, until paste is the consistency of a thick salsa.
2. DO AHEAD: Curry paste can be made 5 days ahead. Transfer to an airtight container; cover and chill, or freeze up to 2 months.