Preheat the oven to 180C/350F and line a 12 hole cupcake tin.

Place the margarine, sugar and lemon zest into a large bowl, or the bowl of your stand mixer and beat on med-high speed until light and fluffy, about 2 minutes.

Add in the eggs and vanilla, scraping the sides of the bowl as necessary, mix until well incorporated, about 1 minute on med-high speed.

Add in flour, baking powder and milk and mix on med-high until you have a smooth, well combined batter.

Place 1tbsp of batter into each cupcake liner, then put 1/2tbsp of passion fruit coulis on top of the batter in the liners.

Then, place another 1tbsp of cake batter over the coulis, to make sure it's covered.

Place in the oven for 18-22 minutes, until rise, golden and an inserted skewer into the centre comes out clean. (Of course, you may end up with a little coulis on your skewer, but it's easy to distinguish between that and raw batter, the coulis will be wet, shiny and yellow).

Once baked, remove from tin immediately and transfer to a wire rack to cool completely. (Yes, they're hot, but this stops the liners peeling away from the cupcakes).

Once chilled, make the frosting: place butter, 2 and 1/2 cups of icing sugar and lemon zest into a large bowl/the bowl of your stand mixer and beat until light and fluffy, about 2 minutes on med-high speed.

Add in 2tbsp passion fruit coulis and mix until well combined. If frosting is still a little runny, add in up to an extra 1/2 cup icing sugar.

Once you have the correct consistency, place frosting into a piping bag, with a large open star nozzle and pipe a swirl onto each cupcake. Alternatively, you can spoon frosting onto cupcakes and smooth over.

Drizzle a little extra coulis onto each cupcakes and top with sprinkles, if desired.

Cupcakes will keep in an air tight container, in the fridge, for 3 days. Take out from fridge 30 minutes before serving.