✓ Preheat your oven to 350°F (180°C) and grease four ramekins with softened unsalted butter.

✓ In a small microwave-safe bowl, melt the white chocolate using short bursts on high power until fully melted; stir well.

✓ Combine the hojicha powder with the heavy cream in another small bowl and mix thoroughly to create a smooth ganache base.

✓ Pour the hot ganache into each ramekin, filling about 2/3 full.

✓ In a large mixing bowl, beat the unsalted butter until light and fluffy, then add the chopped white chocolate, continuing to beat until well incorporated.

✓ Beat in the eggs one at a time, ensuring they are fully integrated before adding another; mix in the egg yolk, sugar, flour, and salt.

✓ Carefully pour the cake batter over the ganache, filling each ramekin almost to the top but leaving a small gap for expansion.

✓ Place the filled ramekins on a baking sheet and bake for 20-25 minutes or until the edges of the cakes begin to pull away from the sides.

✓ Remove from the oven and let cool slightly before dusting with cocoa powder or flour; serve immediately while still warm.