I used this recipe a few weeks ago and mine turned out really good. I just simmered mine...Just hot enough NOT to be boiling. I didn't leave my stove (gas) the entire time I was cooking this because I had no idea what I was doing. Every minute or so it would start to bubble a little and I would stir it and push the green down into the butter/water mix then... leave it for a minute, when it begins to bubble again stir it some more. I cooked mine for about 3-1/2 hours in this fashion and as I said it turned out really good.