how much fruit in the beer?

I brewed 6.5 gallons of California Common (Anchor Steam clone) last weekend and for my inlaws anniversary I would like to add cranberries to recreate a Cranberry Steam Beer my mother-in-law had in college and has told me about ever since I met my wife.

This was my recipe…
9 lb 2-row
2 lb Munich
1 lb Crystal 40L
0.5 lb Victory
1/8 lb Light Chocolate
1 oz N. Brewer (60 min)
1.5 oz N brewer (15 min)
1.5 oz N brewer (1 min)

So… How much cranberry should I add?  I have a 96 oz can of cranberry wine base and a 2 oz bottle of cranberry flavoring.

The general rule is 1-2 lbs per gallon. But I am not sure about cranberries since they can be so tart and bitter.

I’ve heard the same 1-2 lbs ROT numerous times in researching for a Cranberry Lambic. I am going to start on the low side, but I have a much longer time and easier product to tweak with.

Keep in mind you can always add more, but can’t take it away easily. I can blend too, so wasn’t too concerned with it being too fruity. I would suggest using the fruit base (or just frozen berries) and tweaking with the extract.

That is what I have read and have done in the past with fresh/frozen fruit but have never tried cranberry since it can be tart. Plus I have never used fruit flavoring extract.