3 mins is definitely not enough. Ask a friend to sit far away, and when he smells it you know it's done.

As always, I suggest the double-boil vegetable oil method. It absorbs most of the weed. Put a pot with boiling water under a smaller pot with 1/4 cup of vegetable oil, unless your boxed recipe suggests otherwise. Slowly mix cannabis into the oil until for about 10 min, until you can smell it in your entire house. Then mix into your favorite brownie/cookie recipe, works like a charm.