Sugar help

We bought these pastries called choquettes on whim in France and now we're kind addicted to 'em. They are deeelicious. Light and fluffy. Perfect. Tony want's to bake them and he's found a recipe, which he thinks will work. Although the first test wasn't nearly as light and fluffy...

But the thing that has us particularly stumped is that very coarse sugar. We can't find it our local supermarkets and we didn't even find it when we were last in France. Now I'm wondering if maybe you can help us find this kind of sugar in the UK?

Any suggestions? Have you seen something similar?

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