For the invert sugar, I followed directions I found while searching Google. The ingredients include water, sugar, and a small amount of citric acid. You heat it up to boiling, then let it cool. I heated mine a little longer in order to caramelize it a bit.
Nonetheless, I ended up scrapping the recipe I previously posted in favor of a much simpler one. I turned to Jamil's recipe for a Belgian Pale Ale. I didn't use spices, nor did I use sugar or other adjuncts. I used an overnight mash, starting at 152 degrees. Over the course of the eight hour mash, I lost several degrees. It measured around 141/142 degrees in the morning when I began to lauter. I pitched the White Labs 550 (Achouffe) at around 72 degrees (I'm in Texas, and my wort chilling setup isn't that efficient during the summer) and kept the carboy in a closet where the ambient temps were around 78 degrees. The 550 seemed to stall out and left the gravity around 1.030 (starting was 1.056), so I pitched a packet of Safale 05. After another week and a racking, the gravity was down to 1.006, which is a little low for the style. I think I can blame my mashing schedule for this one. The yeast produced a lot of ripe fruit aromas and flavors. I've had a few bottles now. The beer is drier than Rare Vos, but the color is close. Mine has lots of fruit aroma, but isn't quite as smooth as Rare Vos.
I'll continue to play with the recipe and technique - next time I'll probably adjust my mash schedule towards something more conventional - just an hour or two rather than overnight. The yeast seemed to be a pretty good choice though, although if the White Labs 512 (Antwerp Ale) were available I'd probably give it a shot.