Place a rack in the middle of the oven and preheat it to 180°C / 350 °F. Grease a 28 cm or 11-inch tart pan with removable bottom with butter and dust lightly with flour. Discard any excess flour.
sponge cake - wet ingredients
Add butter to a small bowl and melt it in a large bowl beat to combine eggs, sugar, and vanilla. Beat for about 5 minutes on medium speed with an electric mixer until pale in color or doubled in size.
sponge cake - dry ingredients and baking
In a separate small bowl, stir to combine flour and baking powder. Sift the dry ingredients into the egg mixture and fold in using a spatula. Add melted (and cooled) butter and gently stir in. Pour the sponge cake batter into the prepared pan and place it in the oven. Bake for 10 - 12 minutes at 180°C / 350 °F or until the sponge cake is golden-brown and soft. Remove from the oven and set aside for 30 minutes.
Brush the baked sponge cake with syrup to make the cake juicier. Clean the fruit and cut it into smaller pieces if necessary. Arrange the fruits in a single layer over the sponge cake.
For a shiny look and longer cake permanence, make a clear glaze. We bought a packet in the store and followed the package instructions to make it. Here's the one we like to use. Using a brush, evenly brush the fruit on top of the tart.
Place the Summer Fruit Tart in the fridge for 30 minutes before serving. Cut into slices and serve. Optionally serve the tart with whipped cream or a generous dollop of Greek yogurt.