Well this was the availablity of the WY3789 Wyeast Trappist Blend from Orval in their Private COllection (from Brew UK) - WLP510 Bastogne isn't available till May. That and also getting SERIOUSLY into ORval recently whaving found 2 year old bottles at the Sun in Lancaster and 6 month old bottles at the beer shop in the Hawkshead Brewery Beer Hall Beer Shop. Have saved a few bottles and recultured the dregs to be used in this beer.
Recipe Formulation
The recipe was formulated from info on Orval in the excellent Brew Like a Monk and also the recipe in there for the Orval Clone 'La Val'. THis was then adapted based on what I had and thought would work, so EKGs and Aurora as hops rather than the ORval Styrians and Hallertaur or LaVal Perle and GOldings.
Then there was finding (well actually my friend Ben aka The mumbler aka the other monk in the brewing like monks tday) finding Coconut Palm Sugar at the Asian Supermarket in town which looked great:
The taste of pure coconut palm sugar resembles that of brown sugar, yet with more rounded caramel and butterscotch notes, without the metallic ending flavor that brown sugar has. It has a rich flavor. For cooking purposes, it has a very low melt temperature and an extremely high burn temperature. This makes it a suitable sweetener for confectioners.
- http://en.wikipedia.org/wiki/Palm_sugar

so figured on using this instead of candi sugar, however rather than just this made up the recipe to use unrefined cane sugar as well to thin the body and add some flavour as well.
Got Belgian pale Malt from thrifty as my base - seemed appropriate and hopefully a little maltier than pilsener.
So here's the recipe which was formulated with use of BeerAlchemy Touch by our very own Steve Flack. My first 'proper' use of this rather than BrewPal on iPod. It's a little more complex to use and less visual/intuitive but MUCH more powerful and comprehensive.
======================= RECIPE ==================================
"Le Caneton Vert dans les Couches"**
Brewlength:
23litres
Fermentables
GRAINS:
4.5 kg Belgian Pale Malt ( %)
0.35kg CaraRed ( %)
SUGARS
450g Coconut Palm Sugar ( %)
250g Cane Sugar (Unrefined) ( %)
Target OG: 1.060
Target FG: 1.008 (80% attenuation)
Target ABV: 6.4%
Process
Mash @ 64c for 90 minutes
Sparge
60 Minute Boil
Cool to 15c
HOPPING
40g East Kent Goldings (5.1%) - first wort, IBU
10g Aurora (7.8%) - first wort, IBU
25g East Kent Goldings (5.1%) - 15 minutes, IBU
40g East Kent Goldings (5.1%) - Dry Hop in secondary
Boil Additions
Protfloc - 1tsp, 15 minutes
WATER PROFILE:
Baives (high bicarbonate)
Fermentation
YEAST
PRIMARY FERMENTATION:
wY3789 Trappist Blend (alternative = WLP510 Bastogne), 1 litre starter slurry
+
Dregs from 2 bottles of Orval recultured - 1/2 pint starter slurry
Note - these are both mixed cutlures of saccaromyces and brettanomyces with other wild yeasts also included in orval dregs
Process
Pitched at 15c and then allowed to rise to 20c for primary fermentation
Rack to secondary for maturation (may reprime with mixed culture at this stage)
Bottling:
Dregs recultured from 2 bottles of orval: add to bottling bucket
Prime with cane sugar to reach 3-3.5 vols CO2
Bottle condition
** This beer name is a BAD joke - a free sample bottle is on offer to first person who figures it out and posts image + explanation for those confused

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