Be reassured, I'm not actually loosing my temper. I just want to explain another food idiom! La moutarde me monte au nez litterally means "the mustard is getting up my nose". Now if you've ever tried real Dijon mustard (it's much hotter than the one sold in the US; even French brands seem to make it milder for exportation), you can imagine the effect of eating a spoonful of this nose-tickling condiment. When someone is upset and his/her face gets gradually red (you know, like in cartoons!), you can tell that "la moutarde lui monte au nez".
Talking about mustard, I have a new favorite brand! I was looking for Maille mustard the other day at Whole Foods Market but couldn't find it. Maille is excellent (they used to sell it in gigantic jars -1 pound!- at Williams Sonoma. Can't find it there anymore). Not knowing what to do, and not being able to live a few days without mustard, I picked a jar Beaufor's extra strong Dijon mustard at random (well not exactly. It was the "cheapest" -read the least expensive- jar on Whole Foods' gourmet shelves). And it turns out to be the best mustard I've ever tasted overseas! The fact that it is "extra strong" brings it to the the expected spiciness level. Their Moutarde à l'Ancienne (whole-grain mustard) and Moutarde aux Herbes de Provence are exquisite too.