I have a half leg of lamb on the bone that weighs about 1.2kg. I have a recipe for slow roasted with garlic and rosemary. It says it should be in the oven at 120°C for three hours covered with foil, then turn it over and cook covered for another hour. Then uncover, pour red wine over and cook at 150°C for a further two hours. Adding more water if it dries out. I'm guessing I should reduce the cooking time slightly as the recipe is for a 1.8kg leg. I'm not sure how much I should reduce the cooking time. It's obviously not going to be pink but it should still be really tender and fall off the bone. Probably when it goes in at 120 it won't matter as the temp is so low. Should I just reduce the amount of time it is in the oven at 150