Preheat oven to 425°. Line a rimmed baking sheet with parchment paper.
In a large bowl, whisk together flour, 1 cup cheese, baking powder, salt, and pepper. Using a pastry blender or 2 forks, cut in cold butter until it resembles coarse crumbs. Add buttermilk, stirring just until dough comes together.
Turn out dough onto a lightly floured surface, and knead until a smooth dough forms. Using a rolling pin, roll out dough to a ½-inch thickness. Using a 2-inch fluted round cutter, cut 15 scones from dough, rerolling scraps as necessary. Places scones on prepared baking sheet.
In a small bowl, whisk together egg and cream. Brush tops of scones with egg wash, and sprinkle with remaining ¼ cup cheese.
Bake until a wooden pick inserted in centers comes out clean, approximately 12 minutes. Serve warm with Blackcurrant Jam.
Recipe by TeaTime Magazine at https://teatimemagazine.com/irish-cheddar-scones/