idunno if it helps or if it's just my brain that's weird, but i think of it like pound cake. the basic premise of a pound cake is that you have a pound of each ingredient - a pound of butter, a pound of flour, a pound of sugar, a pound of eggs. so you can scale that up and down any way you like; so long as you use the same scale you'll get the same cake. so a mug of butter, a mug of flour, a mug of sugar, a mug of eggs...makes a pound cake, but smaller. (ETA: except technically not because weight and mass isn't the same, BUT THE CONCEPT is what I'm getting at. sorry, i'm tired.)