I suppose the only way to find out is to weigh 20 hazelnuts and then weigh out the equivalent in hazelnut butter to see what the portion size looks like - however I suspect this may come under the same "rules" as the juicing of fruit, in that it's much quicker and easier and therefore less (mentally) satiating to eat a spoon of hazelnut butter than it is to actually chew twenty individual hazelnuts so therefore it's probably not officially acceptable. Having said this, I'd say count it as your HexB for today and maybe do this occasionally if you really must - but just know that when you do, it's a tweak!