Flew into Seattle as I was supposed to do a job there and another in Pasco, so the drive was worth it for the better airline points. Seattle job got cancelled so I drove to Pasco. Saw the sign for Mountain High on the drive over, but it wasn't time for lunch.
Another job came up in Selah, but had the weekend to play so I went back to Seattle to see my cousin and his fiance. Bingo! - lunch time when I came near Mountain High so I stopped.
Exactly what I envisioned - small old building that looks perfectly at home among the pine trees, small crumbling parking area, and a half dozen picnic tables out back.
I got the Mt. Adams minus the relish and mayo and the onion rings. I'm really giving 1 extra star for the location, quaint interior and outdoor seating, because the burger really wasn't that special. The onion rings were pretty good, but far from the best I've had. The milkshake selection did look awesome though.
All in all, If it works out I"ll stop back by on the drive back to Seattle (getting a shake this time - screw the diet).
Was looking for a quick place to stop and have lunch and found this place on Yelp so decided to give it a try. I went thru the Drive thru because it was packed inside. I ordered the Mt Stuart burger (meh), small fries (good), fry sauce (not mixed together...) and a  peanut butter shake (yummy!).  Overall, just ok for the $13 it cost.
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