Slice the soda bread into thin slices, about 1/4-inch, and cut each slice into a rough 2-inch square until you have 16 pieces. Wrap the remaining bread in plastic wrap and store in a cool dry place. Mix the butter and chives together and spread a small amount onto each square. Top with a small fold of salmon and garnish with a sprig of fresh dill.
Preheat the oven to 375 degrees F.
Put the oatmeal into the bowl of a food processor and pulse until finely ground. Pour into a bowl and add the flour, sugar, baking soda, salt, raisins and caraway seeds. Stir well to combine. Pour the buttermilk in and stir quickly until well combined. Shape the dough into a round about 6 inches in diameter and put onto a baking sheet. Place into the top half of the oven and bake 30 to 40 minutes, until lightly brown on top. When tapped, the bread will give off a firm, hollow sound. Remove from the oven and let cool.