Preheat the oven to 400°F. Lightly grease a standard muffin pan; or line with papers, and grease the papers., In a medium-sized mixing bowl, whisk together the flours, baking powder, baking soda, salt, sugar, currants or raisins, and caraway seeds., In a separate bowl, whisk together the egg, buttermilk (or equivalent) and melted butter (or equivalent)., Quickly and gently combine the dry and wet ingredients; honestly, this won't take more than a few stirs with a bowl scraper or large spoon. As soon as everything is evenly moistened, quit; further stirring will cause the muffins to be tough., Spoon the batter into the prepared pan, filling the cups about 3/4 full; the stiff batter will look mounded in the cups. Top with sparkling white sugar., Bake the muffins for 20 minutes, until a cake tester inserted into the center of a muffin comes out clean. Remove them from the oven. Tip the muffins in the pan, so their bottoms don't get soggy. Wait 5 minutes, then transfer the muffins to a rack to cool. Serve them plain, or with butter and/or jam.