Cut butter into flour mixture with a pastry blender or fingertips until mixture resembles very coarse meal. Stir in chives. Make a well, slowly pour in buttermilk while stirring with a fork until dough just holds together. All of the buttermilk may not be needed. Transfer dough to a lightly floured surface and gently knead.
Transfer rounds to an ungreased baking sheet.
Gather scraps together, pat out again and cut remaining rounds. Bake for 10-12 minutes until lightly browned. Spread creamed corn and shallots over potato mixture and top with the remaining potato, sprinkle with extra grated cheese if desired.