I had a similar problem with making grind and brew bean coffee...
The best approach for us was to make my fresh made bean coffee for the day when I run my 2Kw Generator each morning when we are camping off the power grid. It too only takes 5-6 minute to grind the coffee beans and perk up into the thermos container. Revs up my 2KW Honda generator pretty fast when it does it so it is drawing a good bunch of Watts making coffee...
Our style of camping off the power grid requires us to use our generator each morning to re-charge our battery bank so that is the time we also make our coffee for the day...
We have around 255AHs of battery capacity in our battery bank and this does all we want to run in our trailer using a 600watt PSW Inverter for a few 120VAC items and 12VDC items direct connected to the batteries.
All was planned out to reduce our battery bank to its 50% charge state by 8AM each morning when we are allowed to run our 2KW Generator at 8AM at most camp grounds. It takes around three hours of generator run time to re-charge our 255AHs capacity batteries back to their 90% charge so we can do all of this all over again each day. After we do around 12 of 50% to 90% charge cycles we have to do a full 100% charge state on the batteries to keep from doing performance damage which takes around 12 hours to complete. We try to get home before we have to do this procedure as most camp grounds here on the East side of the US don't allow you to run a generator for a continuous 12 hour run.
Always issues hehe...
Roy Ken