Hi James
I get that problem when making curry or stuff with lots of garlic in it. I wouldn't worry too much about it so long as it is clean - the smell will not permeate into your next meal. I made some very strong garlic soup once and it had a very garlicky smell after washing but it was not a problem. I make regular batches of TMX lemonade in it (so addictive!) and that clears any existing smells.
There may be a chemical way of reducing the smell, but I wouldn't know what that would be as I am new to the TM.
JB