Pre-heat the oven to 175°C (350°F).
Melt the butter, then brush some over a small bundt pan (mine was 1 litre / 4¼ cups) with about 5g (1 teaspoon).
Add the remaining butter to a bowl, and stir in the milk and coffee.
In a separate bowl, beat the eggs and sugar until fluffy.
Add the butter mixture to the eggs and sugar, and whisk until well combined.
In another bowl, combine the spelt flour, cocoa powder, baking powder, and vanilla sugar. (see note 1).
Sift this dry mixture into the wet ingredients and gently fold until just combined—avoid over-mixing.
Pour the batter into the prepared bundt pan.
Bake in the lower part of the oven for 30–35 minutes, or until a skewer inserted comes out just about clean.
Let the cake rest in the pan for about 20 minutes before carefully removing it and transferring to a wire rack to cool completely.
Melt the white chocolate and drizzle it over the cooled cake. I like to let it run down the grooves of the bundt design.
Sprinkle with Maltesers, nuts, or any other toppings you prefer. Enjoy!