Preheat your oven to 160°C (140°C for fan ovens). Line a muffin tin with 12 cases.
Whisk the milk and apple cider vinegar together in a small bowl or mug and leave it to sit for 5 minutes. It will curdle and become thicker.
In a large bowl, combine the milk mixture, eggs, egg yolk, melted butter, sugar, and vanilla extract. Mix well.
Add the self-raising flour, cinnamon, all spice, and salt to the bowl then mix well until you have a smooth muffin batter.
Stir in the raisins and orange zest then divide the batter evenly between the 12 muffin cases.
Bake for 20-25 minutes, until a toothpick comes out clean. While the muffins are baking, prepare your apricot glaze by mixing the jam and water together. Brush this on top of the muffins as soon as they come out of the oven.
Transfer them to a wire rack to cool completely.
Prepare the icing by mixing the icing sugar and milk together until smooth. Pipe it into each muffin in a cross shape.
Let the muffins sit at room temperature until the icing is firm then enjoy!