Polly,
I just made some wonderful ice cream, though a far cry from "fat free".

It called for the traditional "custard" to be cooked on stove top (eggs,
cream, etc), and while it was cooking, it called for an entire vanilla
bean, split open lengthwise and the little seeds scooped out.

After it was put together with all of the other ingredients, it called
for an additional 2 tsps of vanilla. I thought that was overkill too,
but the flavor was divine.
Why not split the difference and put in 3? Or...... use two, plus a
vanilla bean.

After I simmered the bean in the ice cream custard, I rinsed it off and
dried it on some paper towels overnight, and then tucked it in a little
plastic container with about 2 cups of sugar. I hear that vanilla sugar
is spectacular for baking.

Patti in Seattle