We were in Mt Cook for 4N and pretty much had all our meals here. It opens at 10:00am which is sleep in friendly and the coffee/food/beer/wine is all very good and portions generous.
This place has personality and a warmth another large venue doesn't along with a pleasant view of the hills. Service is prompt, food tasty and the coffee and hot chocolates excellent. Photos on the walls also provide a history of the place and the books a picture story of the region as well.
I have read that it is expensive, but have to counter that by saying you might pay $NZ23 for the big breakfast, but that's the only meal you will have for the day until dinner. ~$NZ23 is the most expensive breakfast/lunch price with dinner topping out at a little more. When you consider how far it is from everything, it's pretty good value.
I had the mountaineers breakfast and then did a 4+hr hike through the snow and was still full when I returned home. Hamburgers are huge.
For a large portion, good food and friendly service and owners, The Old Mountaineers Cafe is the place to start or end your day.
When in Mt Cook, pop in, have a meal, try the Hermitage and you will find yourself back at the Old Mountaineers more often than not.
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