In parts of Italy (northern, mainly) mashed potatoes are a common accompaniment. I happen to be a big fan of them. Anyway, we happened to have a lunch on the Campo in Siena with some mashed with both courses by happy accident. Classic Italian food:
Primo: Artichoke Pie (wow-good) which came with a little side of mashed. That's pancetta on top of the goat cheese on top of the pie.
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Secondo: Cinghiale stew with a side of mashed
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Nice lunch. Yes, we share them so it's not as much as it seems. Whatever we order, we split each course. Restaurants are fine with that.