(skiing) Partially melted snow with a pulpy texture, making for slow skiing.
1984 November, Richard C. Sailiant, “Ask Skiing [letter]”, in Skiing, page 38:
During late-season skiing, I have encountered ice in the morning and mashed potatoes in the afternoon.
1996 Spring-Summer, Morten Lund, “Skiing Down Those Golden Years with John Jay”, in Skiing Heritage Journal, page 7:
The Eastern ski tribe could confidently expect much ice underfoot while the Western contingent could expect much mashed potatoes around the ankles.
2001 October 1, Paul Parker, Free-Heel Skiing: Telemark and Parallel Techniques for All Conditions, Third edition, Seattle: The Mountaineers Books, →ISBN, →OL, page 185:
I climbed back through the bottomless mashed potatoes as quickly as I could, relieved to see that his ski was off, with his foot pointing in a normal direction— not the skis’.
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