Preheat an oven to 350ºF. Lightly grease a scone pan, or line a baking sheet with parchment paper. In a food processor, combine the flour, sugar, baking powder and salt and pulse to combine. Add the butter and pulse until pea-size crumbs form. Transfer to a large bowl and stir in the currants. In a small bowl, whisk together the egg, cream and orange zest until blended and add to the flour mixture. Using a fork, stir to form large, moist clumps of dough. Turn the dough out onto a lightly floured surface and press together with your hands until the dough comes together. Roll out the dough, flouring as needed, into a 10-inch round about 3/4 inch thick. Cut into 8 equal-size wedges. Press each wedge into a well of the prepared scone pan, or place the wedges 1 inch apart on the prepared baking sheet. Bake until the scones are golden, about 25 minutes. Invert the scone pan onto a wire rack and lift off the pan, or transfer the scones from the baking sheet to the rack. Let the scones cool for 10 minutes before serving. Makes 8 scones. Adapted from a recipe given to Chuck Williams by Judy Rodgers, Executive Chef and Co-Owner, Zuni Café, San Francisco.