Rainbow Cupcakes - She Who Bakes

Ingredients

• 250g plain flour.
• A pinch of salt.
• 1 tsp of bicarbonate of soda.
• 1 tsb cream of tartar.
• 190g caster sugar.
• 115g unsalted butter.
• 2 large eggs.
• 120ml full fat milk.
• 2 tsp vanilla extract.