I have tried the microwave cake packages from the store and a few other variations that ranged from not great to horrid, but today I think I found my "not too bad" microwave mug cake recipe.

I think the original 3-2-1 recipe was 3 parts cake mix, 2 parts liquid (water or milk), 1 min in the microwave. But the one I actually came across is as follows:

3 parts mix
2 parts liquid (I used water)
1 part fat (I only had EVOO & it surpringly didn't leave any olivy taste to it)
Appprox 1 minute in the microwave.

I think the standard measure here is supposed to be 1 Tbsp to make a batter of appropriate volume for the 1 minute in the microwave, but I had a big mug and used a coffee scoop which I think was about 1/8 Cup. It could have used a few more seconds in the microwave at those quantities. It came out like warm flourless torte.

I had some decorating frosting (like from a bag or pressurized can) and after I had to let it cool a bit, I had cake!

You could also try poking a chocolate candy in the batter before cooking to make a lava cake. But this is where I draw the line on quick-n-dirty struggle dessert vs better quality... please don't use Hershey minis. Use a Dove square or a Lindt truffle at the minimum. Or use a piece or two broken off a bar from Lidl or Aldi. Life is too short to eat terrible chocolate.