Preheat oven to 175 degrees C. Line a loaf tin and set aside.
Combine dry ingredients (flour, baking powder, sugar, salt) into a mixing bowl and whisk together.
Combine wet ingredients (olive oil, Greek yoghurt, eggs, vanilla extract) in a separate bowl and whisk well until light and fluffy. Fold in the tea leaves from 4 earl grey tea bags.
Sift dry ingredients into the wet mixture and mix until just incorporated, being careful not to over-mix as the cake will turn out dense.
Spoon the batter into the prepared loaf tin, adding blackberries halfway through.
Bake in oven for 40-50 minutes or until golden and a toothpick comes out clean when inserted into the centre. Set aside to cool.
Remove the loaf from the tin and spoon over the lemon curd, spreading with the back of a spoon.
Combine the sugar and tea leaves from 1 earl grey tea bag in a small bowl. Top the loaf with the sugar coating.
To serve, slice and dollop with Greek yoghurt, a little extra lemon curd and a couple of blackberries.
