- Heat oven to 170°C/150°C fan/Gas mark 3
- Grease and line a 20 cm square tin with greaseproof.
- In a large mixing bowl, beat together butter and sugar until pale and fluffy. Mix in sifted flours and tea until just coming together. Pour into tin and press down until smooth.
- Prick all over with a fork, chill for 30 mins, score into 16 fingers with knife and then sprinkle with flowers and press in.
- Bake for 45-55 mins until just beginning to golden and firm. When removed from oven, go over scored lines with knife again to cut into 16 fingers. Sprinkle with remaining caster sugar.
- Remove from tin to cool completely.