Mettre les pieds dans le plat

This French expression litterally translates as putting (one's) feet in the dish. In the dish???! While there are quite a few steps to making a perfect boeuf bourguignon, we may all agree that jumping in with both feet isn't part of the recipe. So, what could it mean, even metaphorically?

The expression is used to describe someone who brings up a matter that no one wants to discuss - for whatever reason - or a fact that shouldn't have been revealed. It could be the elephant in the room, or any smaller, inappropriate detail that should have been kept private.

The speaker may or may not be aware of having caused any discomfort, and may not feel particularly awkward. In fact, you could decide to put your feet in the dish somewhat intentionnally - to clear up the air or just not realizing that the issue you'd like to discuss may be a sensitive issue for someone else. In that case, your audience would feel uncomfortable but you might not. In that, the French expression has a slightly different meaning than the English to put one's foot in one's mouth, even though both conjure up feet ending up in the wrong place. The English expression definitely implies embarrassment on the part of the speaker; he/she just committed a social blunder by saying something they shouldn't have, possibly about something that is - was - a secret. This would probably be translated into French as faire une gaffe.

Origin

Sometimes metaphors are not what you expect them to be and this expression is a good example of such misconceptions. The expression mettre les pieds dans le plat originally comes from the Provence dialect called "Provençal" and moved into mainstream French in the 19th century. It turns out, in Provençal, a "plat" is an expanse of shallow waters. The metaphor is therefore that of someone stepping in, agitating the water and maybe even moving the mud that sits at the bottom. The troubled waters offer a good visual of the awkward vibes one feels when someone brings up an issue people would rather avoid. Here you go. Nothing whatsoever to do with dinner in the end.

Examples

N’invite pas Thomas au dîner, il a tendance à mettre les pieds dans le plat.
Don’t invite Thomas to the dinner, he tends to bring up inappropriate topics.

Je parle très franchement; je mets souvent les pieds dans le plat.
I speak very frankly, often too frankly.