Preheat the oven to 170°C/325°F/gas mark 3. Thoroughly grease a 10 cup bundt tin, making sure that you get in all the nooks and crannies. Sprinkle it with granulated sugar to coat and tip out the excess. (You can use a 23cm/9 inch square tin instead - grease it and line the base with baking parchment.)
Whisk together the non-dairy milk, non-dairy yogurt and vinegar in a jug; set aside.
In a separate bowl, sift together the plain flour, baking powder, bicarbonate of soda, mixed spice (or pumpkin spice) and salt. Make sure that the raising agents are evenly distributed so that the cake rises evenly.
In another bowl, use an electric mixer to whisk together the softened vegan block butter, light brown soft sugar and grated orange zest until it is light and fluffy.
Whisk in a third of the flour mixture followed by half of the wet ingredients, then another third of the flour, the rest of the wet ingredients then the rest of the flour.
Fold through the mincemeat then transfer the batter to the prepared tin and spread it level.
Bake for 45-55 minutes until the cake is firm to the touch, has begun to pull away from the sides of the tin and a skewer inserted into the centre comes out clean.
Leave the cake to cool in the tin on a wire rack for 20 minutes then carefully flip it out onto a wire rack and leave it to cool completely before glazing and slicing.
To make the glaze, place the sifted icing sugar in a bowl and gradually stir in the liquid of your choice until it forms a thick but pourable glaze. Drizzle the glaze over the cake before serving.