Melt the butter in a large saucepan. Add the sugar and the Rhodes Quality Apricot Jam and whisk over low heat until dissolved. Cool slightly. Whisk in the maas and the vanilla essence. Whisk in the eggs. In a large bowl, sift together the self-raising flour, baking powder and salt into a large bowl. Add the bran flakes and stir to mix. Stir the apricot jam mixture into the dry ingredients and stir to mix to an evenly blended batter. Spoon the batter into a baking pan that has been sprayed with non-stick spray. Bake the rusks in an oven that has been preheated to 180°c for 30 minutes or until a wooden skewer inserted in the centre comes out clean. Turn out onto a cooling rack and leave to cool. Cut into even-sized pieces and place the rusks on a clean baking tray. Do not overlay the rusks but spread out. Slow bake the rusks until dried out in an oven that is preheated to 80° C, or the lowest setting. This can take 2-4 hours. Remove from the oven, cool and store in an airtight container.