In a nonstick skillet over medium-low heat, warm the oil and toast the curry paste, turmeric and chiles (if using) until extremely fragrant, 2 to 3 minutes. Stir and lower heat as needed to prevent sticking.
Step 2
Add the chicken and cook, breaking the meat up with a spoon. Stir to coat the meat in the curry paste and to prevent sticking, and cook until the chicken is opaque, 7 to 10 minutes. If everything is sticking, don’t panic — just add a little water or neutral oil.
Step 3
Stir in the brown sugar, fish sauce and lime zest, and cook just until the liquid’s been absorbed, about 1 minute. Season to taste with more brown sugar and fish sauce. (The chicken should be spicy first, salty second.) Serve at once with desired toppings.