Fine powder causing rig to explode (5,5)

I believe the answer is:

icing sugar

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'fine powder' is the definition.
The definition suggests a singular noun which matches the answer.

'causing rig to explode' is the wordplay.
'to explode' indicates anagramming the letters.
'causing'+'rig'='causingrig'
'causingrig' with letters rearranged gives 'ICING SUGAR'.

Can you help me to learn more?

(Other definitions for icing sugar that I've seen before include "Sweet powder used on cakes etc" , "Cake covering" , "Sweet stuff used for cake topping" .)

I've seen this clue in The Guardian.

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