Combine 8 tablespoons of the butter, egg yolk, sugar, pinch of salt and flour. When ingredients are completely blended, divide the dough in half. Roll each dough half into a cylinder, about 1 1/2 inches in diameter and 6 inches long. Wrap each cylinder in wax paper and then in foil. Refrigerate until hard or for at least 2 hours. Preheat the oven to 375 degrees. Grease 2 cookie sheets with remaining tablespoon of butter. Remove dough from fridge and slice each cylinder crosswise into 1/4-inch rounds. Place the rounds on the prepared cookie sheets, but don't crowd them as they spread during baking. Brush the tops with reserved egg white. Center some sliced almonds on each cookie and bake for 12 to 14 minutes or until the edges begin to brown. Cool on a cookie rack. Delicious served with strawberries simply macerated in sugar.