Mix 1 tbsp red curry paste with 1 tbsp evoo or coconut oil. Use as a rub all over the roast. I usually cook this in the oven, put a little water in the bottom.
When done I use the drippings to make a gravy - heat drippings on the stove and then add 400 ml coconut milk mixed with 1 tbsp thickener (I cheat and use corn starch, but I'm sure you could just do it as a reduction) salt, pepper, a chopped green onion and a 1/2 c fresh cilantro. When thickened add the juice of one lime. Yummy.