Chocolate Cinnamon Donut Icebox Cake

INGREDIENTS

1/2 tsp

Cinnamon, ground

3 tbsp

Cocoa powder

1 tbsp

Cornflour or corn starch

200 g

Dark chocolate, good quality

105 g

Plain flour

Cinnamon donuts, fresh store-bought

60 g

Butter, unsalted

600 milliliters

Thickened or heavy cream

Grans (1/4 cup + 1 tablespoon) caster sugar