With the wire mesh thingy....and just get ground coffee at your supermarket and refill the wire mesh basket full and run 8 oz water thru the boiler twice for less strong.
Works well for me and much less expensive than buying the K-Cups.
Bed Bath and Beyond has the wire mesh baskets and the K-Cups also,
I bought a Keurig about a year and a half ago. Bought the wire mesh filter at the same time so have never used the K cups. I have tasted them since friends/family all buy them but haven’t tasted any I like. They all taste like instant coffee to me.