I recently received as a gift a pack of pre-ground coffee that was supposed to be incredible, but I just can't get it to work. I'm still getting used to my Moka pot, so its normal that I don't get a new coffee right in the first try, but this one is proving a challenge. No matter what I do, it ends up over-extracted (quite bitter).
My first suspicion is the grind, it doesn't look consistently sized:
I'm not certain, but I think this grind is the main culprit of a lot of coffee sediment going through:
I'm somewhat used to seeing a bit of sediment in my Moka coffee, but this is an outlier and I'm betting it is related to the bitterness. After trying different flame sizes (i.e. temperatures) and different amounts of water and seeing no change, I'm wondering if there's something else I should do, or some specific temperature/water level/method I should try - like interrupting the extraction midway with cold water as I've seen some people recommend.
Also, the extraction process is sputtering quite a bit, the coffee goes out on high pressure from the start. Maybe despite most of the coffee being quite coarse, it's still clogging the filter with the smaller particles? I'm definitely not tampering, don't even fill all the way through (like 90% filled).
Is my analysis correct and the grind is the biggest problem, or is there something else I should experiment with my Moka pot that may work? Should I reserve this coffee for some other method like pouring over, or just give up?



