When I make a Thai red or Panang curry using lamb, the meat never comes out REALLY tender, and I'd like to know what I'm doing wrong. Here's what I currently do. For the meat, I've tried using the generic "diced lamb" sold in the shops, or lamb leg cutlets, a cut referred to as "escalopes" (but don't really know where that cut comes from), and boneless rolled shoulder which I then cut into chunks (versus sliced). I then marinade the meat for about 45 minutes in coconut milk, Kaffir lime leaves and a dash of fish sauce, sometimes a little freshly ground cumin and corriander seeds. After preparing the curry sauce, I add the lamb and slowly cook it on the top of the stove for about an hour with the cover off, being careful not to ever let it boil. I'm really pleased with the flavour of my curry, but the meat tends to be a bit chewy and doesn't melt in the mouth as I'd like. Am I using the wrong cuts of meat, cooking too long or too slow? I've also tried using a lid and cooking in a slow oven, but 2 times the curry sauce kinda "curdled" for lack of a better word. We normally like lamb pink (as in roast leg of lamb, for example), so maybe it would be good to cooki something like rack of lamb or lamb chops separately, and pour the sauce over would produce a better (though less authentic) result? Any advice would be appreciated!