What's your favorite boutique speaker maker

Watkins would be another for monitors.

Burmester, followed by Canton and ELAC.
M. 🇿🇦 

Sanders Sound

Verdant Audio.  I have had the Nightshades for a little more than a month and I like them more every time I listen to them

I understand that when someone discovers HiFi, and they move from a box store item to a HiFi speaker, they likely think they have a "boutique" speaker. My perspective is as an insider, reviewer, so my judgement of what a boutique speaker is will vary significantly from many. 

Magico, Magnepan, Canton, ELAC, Rockport, Egglestonworks,  and the like I do not consider boutique. Specialized, and in some cases customized, i.e. HiFi, but imo not boutique. Maybe when they were first getting started, but now they are major players. When you kick out dozens to hundreds of speakers a year, imo you are not boutique- you are a factory with an established product. 

Imo, "boutique" is way closer to unique. Once production scales, it's farther from boutique. (Of course, companies will potentially wish to market themselves as offering boutique products if that is advantageous to them, even though mass produced.) 

Soon I will have a demo of a speaker made by a man at his home, literally., who has been building speakers for 15 years. He actually makes the ribbon drivers in his speakers, and it takes 6-8 weeks to make the speaker. That is an example of what I would call a boutique speaker, not mass-produced products, or ones that use off the shelf drivers, potentially with average internals (Not suggesting all the companies mentioned above do so, but some may cut corners and diminish their sound quality).  

I am reviewing a DAC that I would still consider in terms of design and production to be closer to boutique than produced in larger quantities. It's unusual, hand assembled, and comes from a smallish operation. I'm sure someone else would consider a Bryston or Benchmark DAC to be boutique. 

Responses to this will be all over the board. What I find interesting is that there is no sure way to determine whether a mass produced product will outperform the boutique product, except by actual comparison. All the rest is puffery.