Preheat the oven to 350°. Butter two 9-inch round cake pans and line the bottoms with parchment paper; butter the parchment paper. Coat the pans with flour, tapping out any excess.
Melt the white chocolate in a small saucepan set over a pot of barely simmering water, stirring occasionally. In a medium bowl, whisk the flour with the baking powder, baking soda and salt. In a large bowl, using an electric mixer, beat the butter with 1 1/4 cups of the sugar until fluffy, about 2 minutes. Add the vanilla, then beat in the egg yolks, 1 at a time. Beat in the melted white chocolate. Add the dry ingredients in 2 batches, alternating with the buttermilk.
In a medium bowl, beat the egg whites until soft peaks form. Gradually beat in 1/4 cup of the sugar until the whites are glossy and firm. Stir one-third of the beaten egg whites into the batter, then fold in the rest until no white streaks remain. Scrape the batter into the prepared pans and smooth the tops. Bake for about 35 minutes, or until springy and golden and a toothpick inserted in the centers comes out clean. Let the cakes cool in the pans for 10 minutes, then run a knife around the edges and invert them onto a wire rack to cool. Peel off the parchment paper.
In another bowl, beat the cream and crème fraîche with the remaining 1 tablespoon of sugar until firm peaks form. Place 1 cake layer on a serving plate and spread with half of the whipped cream. Top with half of the strawberries and the second cake layer. Spoon the remaining whipped cream over the cake, swirling it decoratively. Top with the remaining strawberries. Serve with the Strawberry Star-Anise Sauce.
The cake can be refrigerated for up to 2 hours.