The answer to these things is usually something like clean it with a lemon or vinegar. Whether the resultant smell will be better or worse I don't know. Or maybe stand it in a bowl of boiling water with some bread- the bread may soak up the onion smell
Well you could try soaking it in bleach water, even tough it's a wooden board. Alternatively you could buy another chopping board for buttering your toast on. I have four. Different colours for different things.
I'd opt for lemon juice also...which *might* work. Otherwise-get a plastic chopping board.
Come to think of it-baking powder may work-it's good at drawing/absorbing bad smells out of things.
Brilliant, i'll give all those things a go and see how I get on. Don't want to get a new board if i don't have to as a decent one isn't cheap. In the mean time I'll do the toast on a plate!
i agree with pastafreak, on the cleaning issue and also think you should use a plastic or glass chopping 'board', or maybe get a wee board just for the onions.
make a paste with white vinegar, salt and bicabonate of soda (It'll fizz like mad at first) spread over your board and leave overnight, wash off in the morning in hot soapy water and you should find the smell gone.
i have three chopping boards.
Good quality one for sandwiches, bread etc..
I have 2 for chopping food, onions carrots and all sorts.
if they gets a bit pongy, i soak in diluted bleach and its fine --no smells.
Apology! Forgot your boards are wooden!
i wouldnt have a wooden board for that same reason yrs ago.
I find plastic so much better and easier to clean with diluted bleach x