Suggestions needed for Dark belgian recipe

I am planning a belgian strong using the yeast cake from a belgian double. I have come up with a simple recipe from looking through multiple recipes and using what is available from my local brew shop. Please let me know if there are any suggestions, as I plan to brew this weekend.

10 lb light malt extract
3 lb light brown sugar
1 lb Briess caramel 60

2 oz fuggles @ 60 minutes
1 oz Hersbrucker @ 30 minutes
1 oz Hersbrucker @ 10 minutes

White Labs Trappist Ale (WLP500) cake from previous batch

Sounds good. I usually only do a -60min hop addition on my dark strongs, but nothing wrong with some later additions.

It'll probably finish well below 1.023, though. I'd guess around 1.010, because of the sugar. So it'll be a lot stronger than you think it will be. If you don't want it to be 12% ABV I'd scale back the ingredients a bit.

Thanks for the advice. I used beer calculus for the formulation development for this recipe and the Belgian dubbel. It projected that the dubbel FG would be 1.014 and I was down to 1.011, so the sugar must bring it down some. Would you suggest that I cut the brown sugar to 2 lb or lower to keep the alcohol at 11% ABV (within style guidelines)?

I just made one that came out really nice. A little Special B works well for some of the darker-fruit overtones, maybe a half-pound at most. It's like a REALLY dark crystal malt, so you should be able to steep it with no problems. You're only at 14 SRM, the Special B will add a little more color as well, get you a little darker.

Also, the dark liquid candi syrup makes a really nice addition (same role as the regular brown sugar, but it should be better).

I used Briess Extra Special Malt in my dubbel recipe since my local shop didn't stock the special B I was planning to used. Do you think that would work? Should I go w/ 1/4 or 1/2 lb? My shop doesn't have candi syrup. What do you think about 1 lb light brown sugar and 1 lb dark candi sugar?

I would scale the fermentables back evenly. I usually go with 15-20% sugar in my big Belgian beers.

If you can't find Special B, I'd use the darkest crystal you can find.

The dark "candi" rocks are a waste of money, IMO. You can make your own candi syrup without much trouble. There are a few threads around about that. Here's my own. It's still a work in progress, but I've gotten some interesting results so far.

https://www.homebrewtalk.com/f12/candi-syrup-experiment-trying-clone-d2-220882/