Japanese Christmas Cake

Name: Japanese Christmas Cake
Ingredients: 1 teaspoon cultured unsalted butter ((for buttering pan)); 75 grams cake flour; 4 large eggs; 100 grams granulated sugar; 1 teaspoon vanilla extract; 50 grams cultured unsalted butter ((melted)); 1 cup heavy whipping cream ((at least 37% fat)); 2 tablespoons powdered sugar; 80 grams strawberries ((4 small berries)); 1/2 cup heavy whipping cream; 1 tablespoon powdered sugar ((plus more for dusting)); 120 grams strawberries ((6 small berries)); silver dragées (optional)