Traditionally, the beef for this type of curry is braised rather than briefly fried. Accordingly, it is better to use pieces from the leg, breast or shoulder, areas with a higher percentage of connective tissue and collagen. To make sure the meat was still butter tender, I vacuumed it with some coconut milk and lemongrass and cooked it sous-vide at 80 degrees for about 220 minutes, let it rest and then seared it hot and crispy on all sides before slicing it thinly and adding it to the curry just before serving.
So while the leg of beef simmered very slowly towards its perfect cooking point, I had more than enough time to take care of the curry paste. A central ingredient in Gang Panaeng is peanuts. Since this time I strictly followed a recipe from my absolute favorite book of Thai cuisine, David Thompson’s Thai Food, unsalted peanuts were first boiled for a good 30 minutes in a little water to make them as soft as possible and easy to puree. To the peanuts then add 6-7 red chilies, 1 tsp. coriander root, 1.5 tbsp. galangal, 1 tbsp. lemongrass, 3 tbsp. chopped and previously sweated shallot, 2 tbsp. garlic, plenty of nutmeg.
Now either pound the paste in a mortar (better) or puree it in a food processor (faster). Then (and just before the end of the cooking phase of the beef leg) slowly fry about 4EL of the paste in coconut oil for 10 minutes. The remaining paste can be stored under some olive oil and cling film in the refrigerator for 10 to 14 days. As soon as the paste begins to release its delicious aromas, you can slowly add 1.5 tablespoons of palm sugar, then 2 tablespoons of fish sauce and 3 kaffir lime leaves and more chopped chilies (to taste). Then pour everything with 500ml of coconut milk and the stock of the vacuumed leg of beef.
Finally, add the thinly sliced beef shank and a large handful of chopped Thai basil and cilantro and serve with plenty of rice.
