How about Mustard seeds/flour in the mash?

Anyone ever put this spice in beer as an adjunct?

I know they make mustard with commercial beers
so it is not like they do not go well together…

Not mustard seeds in the mash; I’d use them late in the boil like coriander.  There are commercial beers that use mustard seeds (Wostyntje, from Belgium).

Thanks Gordon, did you ever try one of those?

It’s been awhile.  I’m not sure I got good examples, though.  It’s a little hit-or-miss with small Belgian breweries.  I should try to get one over there sometime.  Seems like I got some of the flavor, but don’t remember the beer as being remarkable.

You can check what people say on the rating sites (YMMV).

I’ll agree with Gordon that the beer as I remember it wasn’t terribly remarkable.

A few years back my club’s Iron Brewer competition required mustard seeds. (I think Gordon was one of the judges.) Almost everybody used them as a late boil spice. They provided a nut-like taste that some described as almond. Mustard seed doesn’t taste anything like prepared mustard. The condiment is a vinegar extract. Pop a seed in your mouth (don’t be afraid  ;D) and you’ll know exactly what you’re going to get.