Glitzy Eurovision iced biscuits

Tins, packets and jars

gel food colouring (colours depend on the flags being drawn)

270g/9Â¾oz plain flour, plus extra for sprinkling

360g/12Â½oz icing sugar, sieved, plus extra if needed

1 tsp vanilla bean paste (or extract)

180g/6oz salted butter, softened

60g/2Â¼oz egg white (from approximately 2 free-range eggs), plus extra if needed

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