70g/2½oz fresh root ginger, peeled and sliced
2 pink grapefruit, juice and zest only
3 white grapefruit, juice and zest
1 red grapefruit, juice and zest
2 tsp lemon juice
250g/9oz plain flour, plus extra for dusting
60²µ/2¼´Ç³ú caster sugar
300²µ/10½´Ç³ú caster sugar
½ tsp ground cinnamon
2 tbsp cornflour
3 tsp ground ginger
65²µ/2â…“o³ú icing sugar
½ tsp salt
pinch salt
125²µ/4½´Ç³ú butter, chilled and cubed
70g/2½oz unsalted butter, cubed
1 small free-range egg, beaten
3 large free-range eggs
140g/5oz egg whites, at room temperature
2 large free-range egg yolks
5 large free-range egg yolks