Margarita Cupcakes

INGREDIENTS

• :
• 1½ cups all-purpose flour
• 1½ teaspoons baking powder
• ¼ teaspoon salt
• ½ cup unsalted butter, at room temperature
• 1 cup granulated sugar
• 2 eggs, at room temperature
• Zest and juice of 1½ limes
• 2 tablespoons tequila
• ¼ teaspoon vanilla extract
• ½ cup buttermilk
• 1 to 2 tablespoons tequila
• 1 cup unsalted butter, at room temperature
• 2¾ cups powdered sugar
• 1 tablespoon lime juice
• Pinch of coarse salt