First make the peach topping. Pour the melted butter into the base of a 9" springform tin. Sprinkle the sugar over the butter and spread it around evenly. Place the sliced peaches in an even layer on the sugar butter mixture. Set aside. The butter may leak out a bit in a springform tin, so make sure to place it on a baking tray to catch any drips
Preheat the oven to 175 C.
In a large bowl, sift the flour, baking powder, baking soda and salt. Set aside.
In a mixing bowl, beat the butter and sugar with a hand mixer till light and fluffy, about 2 minutes. Add the eggs and vanilla and beat till combined.
Now stir in the yoghurt and flour mixture alternately, starting and ending with the flour so that batter doesn't curdle.
Fold with a spatula or beat on low speed with the hand mixer till you have a smooth batter but do not over-mix. Stir in the peaches gently. The batter is fairly thick.
Spoon the batter on top of the sliced peaches and smoothen the top. Bake for 40 to 45 minutes, covering the top loosely with foil if it's browning too quickly. Bake until the top is golden-brown, and a toothpick comes out clean. It may crack a bit but will not dome.
Allow the cake to cool in the tin for 5 minutes.
Now remove the sides of the springform tin and place a platter or sturdy wire rack (to prevent sogginess) directly onto the surface of the cake, then quickly invert. Remove the base of the springform tin and voila, you have a lovely caramelised peach topping!
Allow the cake to cool for about an hour, then slice with a sharp knife and serve with whipped cream or vanilla ice cream while still slightly warm. Store in the refrigerator for 4 to 5 days. Best eaten warm or at room temperature. Happy baking!