It's better to add some oil to the hash before heating it, or if you don't, leaving the prepared yog in the fridge overnight. For it to work best the THC has to emulsify with the fat, either with the oil when you heat it on the spoon, or slowly with the fat in the yoghurt. It tastes fine, if you use yog with a strong flavour - I find black cherry flavoured yoghurt works well. Oh, and make sure it's a bio youghurt (one with active cultures) as this seems to work better. I'm not sure about how many grams to use, I don't work in grams, but I find a good 2 spliffs worth should be about right.

Enjoy