I am going off filter coffee, you know the kind you get from drip coffee makers.
At home and now in the office I use a French style cafetiere. Using a coarser ground coffee, it’s as quick and easy as making instant coffee, but because the metal mesh allows the grounds to be in direct contact with the water, you capture more of the essential coffee oils and coffee flavour.
At home I use a medium sized cafetiere, but at work I have a single cup version.
It should be said it does take more effort to clean than drinking instant coffee or using a drip filter coffee machine, but for me that’s a price worth paying for a decent cup of coffee.