Anna Olson's Pink Lemonade Cupcakes

Ingredients

• 1 ½ cups all-purpose flour
• ⅔ cup granulated sugar
• 2 tsp baking powder
• ½ tsp baking soda
• 1 lemon, finely zested
• ½ cup vegetable oil
• ½ cup buttermilk
• 2 large eggs
• 1 large egg yolk
• 2 Tbsp fresh lemon juice
• 1 tsp vanilla extract
• 1 ½ cups unsalted butter, room temperature
• 6 cups icing sugar
• Finely grated zest of 1 lemon
• ½ tsp fine salt
• ¼ cup whipping cream
• 3 Tbsp fresh lemon juice
• 1 Tbsp vanilla extract
• Pink and yellow food colouring gels
• Pink or yellow sprinkles or candies, for décor