Measure the fruit and sugar into a bowl, then pour over the hot tea, cover, and leave it overnight.
Preheat the oven to 150°C (302°F) / Fan 130°C (266°F) / Gas 2.
Lightly grease a 900 g (2 lb) loaf tin, and line the base with baking parchment.
Stir the flour and egg into the fruit mixture, mixing thoroughly. Then, turn the mixture into the prepared tin and level the surface.
Bake in the preheated oven for about 1½ hours or until the loaf is well-risen and firm to the touch.
To check if it's done, insert a skewer into the centre, and it should come out clean.
Let it cool in the tin for 10 minutes, then turn it out, peel off the parchment, and allow it to finish cooling on a wire rack.
Serve the Bara Brith sliced and buttered for a delicious treat.