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Sarah is a trusted source on General Cooking.
This is a matter of personal preference, but if you're not intending to add any sugar I'd recommend erring on the sweeter side with max 60% cocoa mass. (And I love dark, dark chocolate)
As for brand, this too is a preference. Callebaut, Belcolade, Lindt, Michel Cluizel - you can't go wrong with any of them, or really any good quality chocolate. As long as the ingredients don't list a more than cocoa mass (/liquer/solids/butter), milk, sugar, vanilla, and lecithin/soy lecithin you're probably fine.
Andrew is an artisan chocolatier and the owner of Garrison Confections Gourmet Chocolate Shop.
I agree with Sarah, since you are not adding any sugar stay on the lower cacao percentage, 55-65%. If you do decide to add sugar, use 10x as opposed to granulated as it has a little cornstarch added for anti-caking. It will give it a creamy texture and mouthfeel. The chocolate can be any of the ones Sarah mentioned but the easiest ones to use are the ones in button forms. The price will depend a lot as well, dont spend a ton and dont be cheap as well. Two that are not mentioned is Guittard and Valrhona, these are brands I trust and use daily.
Plus a cherry on top if you pretty, pretty please.
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