Shallots

Shallots are a small type of onion which grow in clusters, like garlic.
They have a characteristic tapered shape and thin, usually copper coloured skins. 
You could use them like-for-like in recipes that call for red or white onion but as they have a more delicate, sweet flavour which diminishes with heat, they are best savoured raw in salsas or dressings such as mignonette, the classic vinaigrette made to accompany oysters.
They will add a gorgeous allium-hum without any of its sting.
If your meal were a piece of music you can think of them as providing a top note, whereas treacly, slowly caramelised onion would be a steady bass. The Thai word for shallot is “hom”, which translates to ‘good smell’.