Lemon curd

I have a couple of fairs coming up this weekend, the last of the summer really and I'm just trying to get myself sorted for them. I had an order for 2 jars of lemon curd from a lady who can't make the Sunday event, but has asked someone else to collect them from me.
I have a bit of curd left, but was going to make a lemon tart with it in my baking tomorrow ( all to be donated to the charity fair I'm at on Sunday)
So this morning I've made a new batch, it's quite an easy recipe, none of this double boiler lark, just patience and calmness needed.

The basic recipe follows, although I do tend to deviate from the exacting measurements depending on the size of the eggs or lemons I'm using, sometime I add a couple extra of one or each of them.

Into a pan, put -
170g unsalted butter and put a low heat to melt slowly.
While that's happening, finely grate the zest off 6 lemons and then juice them, add the zest and juice to the pan ( then save the lemon shells and pips in the freezer to make homemade pectin when I have a bit of time)
Chuck in 400g of white sugar and stir it all away, keep the heat low.
Break 6 medium-ish eggs into a jug and give them a good beating with a fork, then pour through a sieve into the pan.
Whisk gently to amalgamate the whole lot, then change over to a wooden spoon, and stir gently and turn the heat up a fraction.
Then it's basically a job of getting your 6 small jars ( condiment size is about right, you know, the ones that supermarkets tend to sell their tartare sauce/ mint sauce etc in) ready and sterilised whilst very regularly coming over and stirring the curd for a minute or two.
It normally takes about the time to thicken that it does for me to wash out my jars and stick in the oven for 15 mins to dry and sterilise.
It's ready when it's thick and if not stirred, the occasional bubble rises from the bottom ( just off boiling)
That's about it, I pot it up using cellophane discs dipped in brandy under the lids and store it in the fridge due to its ingredients, and it's fine for a good few months, but once opened, needs to be used relatively quickly.