First, I've a few personal constraints:
- I've to drink decaf (was in hospital because of caffeine).
- I'm traveling a lot so no grinder, no scale, I rely on store ground coffee.
Typically I buy the Lavazza DEK:
When at home, where I have a scale, but no grinder, I have tried to follow a few recipes from competitions. Also I've tried to follow James Hoffman's "Ultimate Aeropress recipe" (https://www.youtube.com/watch?v=j6VlT_jUVPc&t=144s), all with that coffee and they all taste like bitter and thin.
I manage to make very nice coffee with it but it always takes very little water and very short steep time. All these recipes that call for a lot of water and long steep times taste awful with that specific coffee.
My guess is that it has to do with the grind which is just not compatible with these recipes.
When it comes to grind size, for example the James Hoffman recipe says "ground at the finer end of medium"... but what is 'medium'? Is there a real scale for this? How can I know where the coffee I buy stands when it comes to grind size? Or, is it possible that the pre-ground coffee has an inconsistent grinding size? or could it be that decaf has to be brewed differently?