I'm sure there's an easier way to do this, but if not can you help with what I'm trying my best to fix!

I have two rows of data, A+B. It goes to B500. This data is pulled from another data set by a formula and can be blank.

I need them to be combined into one row, using a formula so instead of:

eggs - milk
chalk - gammon
peas - suits

it will read

eggs
milk
chalk
gammon
etc

I've tried copying dragging A1, B1, A2, B2 etc down but it skips rows and restarts on whatever row it's on. Any idea?