Combine apricots and boiling water in a bowl; cover and let stand 30 minutes. Drain well.
Preheat oven to 375°.
Combine the rehydrated apricots, buttermilk, and next 5 ingredients (buttermilk through almond extract). Lightly spoon flour into dry measuring cups; level with a knife. Combine flour and next 4 ingredients (flour through salt) in a bowl. Add apricot mixture, stirring just until moist.
Pour batter into a 10-inch springform pan coated with cooking spray. Sprinkle with 2 tablespoons sliced almonds and granulated sugar. Bake kuchen at 375° for 30 minutes or until a wooden pick inserted in center comes out clean. Cool on a wire rack.