This is what I did in the end:
Ca Plane Belgian Singel
Grist:
4Kg Lager Malt
1Kg Munich Malt
Hops:
40g Goldings FWH 4.6AA
50g Saaz at 15 mins 3.5AA
20g Saaz at Flame Out 3.5AA
(I couldn't resist an aroma addition in the end - the Saaz hops smelled so nice)
Yeast: 2l starter of Wyeast 1214 Belgian Abbey - Chimay yeast apparently
Water: I just knocked the alkalinity down to about 20mg/l with CRS and then added a teaspoon of Gypsum to the mash and another to the boil.
Here's the porn:

2l yeast starter went on earlier in the week. It was nicely fermented out by last night.

Grain - Lager malt and Munich

Mashed in. 65.3C - I plan to leave this for 3 hours, by which time it should be down to 62C or so to give a highly fermentable wort.

Mash pH - about 5.1-5.2

Another mash pic

First wort hops (Goldings) and a teaspoon of gypsum

First runnings

These Goldings smell great

And the Saaz for the later additions

Getting up to the boil. I can't take rolling boil shots as the camera can't focus through the steam....

Running off through the chiller and pump into the FV

Hopsntrubnstuff...

Yeast pitched, a bit of yeast vit and a good old aeration session with a (sanitised) paint mixer on a drill

Final amount - its a bit more than my 21L planned brew length as the yeast starter still had some liquid left in it. This yeast didn't settle right out after fermentation like others have, so I couldn't pour off all the starter beer - I ended up with about 1l of liquid from the 2l starter.

And finally - the result. This is about 1052, but I was aiming for 1049 so I diluted the wort in the FV down to 1049 at 21L.
Anyway.....another one bites the dust! Time for a beer....