the best I've had, and I'm by no means an expert, were at "Funny People" coffee shoppe--http://www.hiptravelguide.com/amsterdam/php/reviews.php?op=showcontent&id=57 but, that was several years ago, and since then I tried it once and it was "ok" but not the best--so, maybe you should ignore my post--lol. They did remodel their shoppe, who knows if their SC is still as good?
Coffeshop Baba. I usually start with a spaceshake, space cake and nice cup of tea. When the biscuit you get with with the tea starts to taste REALLY good you know everything is working. Then its time to smoke that grass you bought at Greyarea and stare at the ceiling.
Went to amsterdam the second week of november, purchased and ate two space cakes from baba,no buzz at all.Purchased two from Rokerij, not a thing.Damn great time had ,however.I'll stick with the crystal clear from katsu!