Preheat the oven to 190ºC/375ºF/Gas mark 5. Oil a 12-cup muffin tin with vegetable or line it with muffin paper cases
Sift the flours, bicarbonate of soda, salt, cinnamon and ginger into a mixing bowl. Add the caster sugar and mix together
In a separate bowl, whisk together the egg whites then pour the milk and the oil and mix together
Mash the pineapple chunks, then add to the egg mixture
Add the carrots, sultanas and walnuts and stir together gently
Add the fruit mixture to the flour mixture and gently stir together until just combined. Do not over-stir the mixture - it is fine for it to be a little lumpy
Divide the mixture evenly between the 12 cups in the muffin tin or paper cases (they should be about ⅔s full)
Transfer to the oven and bake for about 25 minutes or until risen and golden
While the muffins are in the oven, make the topping. Put the Quark into a mixing bowl with the caster sugar, vanilla essence and 1 teaspoon of the cinnamon. Mix together well, then cover with cling film and transfer to the fridge until ready to use
When the muffins are cooked, remove them from the oven, put them on a wire rack and leave to cool. When they have cooled to room temperature, remove the topping from the fridge and spread some evenly over the top of each muffin
Lightly sprinkle over the remaining cinnamon and serve