Preheat the oven to 350°F.
Grease a 9-inch springform pan with butter.
Halve the apricots, remove the pits, and cut the halves into quarters.
In a bowl, cream together butter, sugar, and vanilla extract until light and fluffy.
Beat in the eggs one at a time, mixing well after each addition.
In a separate bowl, whisk together flour, baking powder, and salt. Gradually add to the wet ingredients, mixing until just combined.
Stir in the yogurt until smooth.
Pour batter into the prepared springform pan and arrange apricot pieces evenly on top. Press them lightly into the batter.
Sprinkle sliced almonds over the top and dust with the additional tablespoon of sugar.
Bake for 40 minutes, or until golden brown. Test for doneness with a toothpick.
Let the cake cool slightly before removing it from the pan.
