- 1 cup all-purpose flour
- 1 teaspoon baking powder
- 1/4 teaspoon salt
- 5 tablespoons unsalted butter, softened
- 1/2 cup superfine sugar
- 1/2 teaspoon pure vanilla extract
- 1/4 cup milk
- 1 large egg, beaten
- Rose Petal Jam
- 6 ounces white chocolate, broken into small pieces
- 2 tablespoons unsalted butter
- 1/2 tablespoons canola oil
- 1/2 teaspoon fresh lemon juice
- Preheat the oven to 350°. Butter and flour an 8-inch-square cake pan. In a bowl, sift the flour, baking powder and salt.
- In a bowl, using a hand-held electric mixer, beat the butter and sugar until light and fluffy, about 3 minutes. Beat in the egg and vanilla until smooth. On low speed, beat in the dry ingredients alternately with the milk in three parts, beginning and ending with the dry ingredients.
- Scrape the batter into the prepared pan and use a rubber spatula to smooth the top. Bake in the middle of the oven for about 25 minutes, or until a cake tester inserted in the center comes out clean. Let the cake cool slightly on a rack set over a baking sheet, then run a knife around the edge to loosen it. Unmold it and place right side up on the rack.
- Mix the Rose Petal Jam well to loosen it. Using a metal icing spatula, spread the jam on the top of the cake.
- In a small heatproof bowl set over a saucepan of barely simmering water, melt the white chocolate and butter; do not allow the chocolate to get too hot. Remove form the heat and stir to blend. Stir in the oil and lemon juice until smooth.
- Pour the white chocolate glaze over the cake, covering the top and sides. Use the icing spatula to smooth the glaze over the top and sides. Transfer the cake to a platter and refrigerate until the glaze is set, about 20 minutes. Cut inot squares and serve.
The cake can be made 1 day ahead; cover and store at room temperature.