Preheat oven to 180 degrees C. Place 18 muffin cases or large patty pans into 2 muffin trays.
Make cake mix according to directions then stir in the apple.
Place 2 tablespoons of the mix into each muffin case then drop 5 frozen raspberries into middle of mix in each muffin. Cover each evenly with rest of mix.
Cook for 20-25 minutes until golden on top and a skewer comes out clean. Cool.
In a heat proof bowl over a saucepan of boiling water, melt the white chocolate. Swirl over muffins and let set before serving.