Preheat the oven to 170°C fan/375°F/gas 5. Place the sugar, oil and vanilla extract in a large bowl, then beat with an electric mixer (I prefer the free-standing type) for 1 to 2 minutes, until well combined. Mix the yoghurt and vinegar together in a bowl, then add to the mixture and beat for 1 to 2 minutes. Add the remaining cupcake ingredients and 1 teaspoon of fine sea salt, then whisk until smooth and just combined. Fill the paper cases two-thirds full with mixture, but don’t bother to smooth it out. Bake for 20 minutes, or until they spring back when touched. Leave to cool, transferring to a wire cooling rack after 5 minutes.
Meanwhile, make the icing. Beat the soya spread with an electric mixer for 1 to 2 minutes, or until smooth. Sift the icing sugar into a large bowl, then add to the soya spread in two stages, beating well between each. Add the vanilla extract and a small splash of water, then whisk for a further few minutes, or until silky smooth – if it’s too stiff, add a splash more water to loosen. Once the cupcakes are cool, decorate them with the icing and add a few sprinkles too if you like – whatever takes your fancy – then enjoy.