Preheat oven to 325°F. Line your cupcake pan with cupcake liners and spray the paper cups with non-stick spray.
In a large bowl, whisk together dry ingredients: flour, baking powder, and salt.
In the bowl of an electric mixer with paddle attachment (medium-high speed), cream butter and sugar until light and fluffy (4–5 minutes).
Reduce mixer to medium speed and add eggs one at a time, then scrape sides.
Add wet ingredients: lime juice, lime zest, tequila, yogurt, and vanilla extract.
Lower mixer to low speed and gradually add dry ingredients. Mix just until combined—don’t overmix!
Use an ice cream scooper to divide cupcake batter evenly among the cupcake form liners (¾ full) and bake 25 minutes, rotating halfway. Cupcakes are done when a toothpick or sharp knife comes out clean and the tops are lightly golden brown.
Brush the Top of CupcakesCool cupcakes for 5–10 minutes on a wire rack, then brush the tops of the cupcakes with 1–2 tablespoons tequila. Frost the CupcakesOnce cooled completely, frost with tequila-lime buttercream. To make the tequila lime buttercream, in the stand mixer (whisk attachment), beat butter on medium-high speed for 5 minutes. Gradually add powdered sugar until fully incorporated, then whip on medium-high speed for 30 seconds.
Add lime juice, tequila, vanilla extract, and salt. Whip until smooth. Add more sugar if too soft.
Transfer frosting to a pastry bag with Wilton 1M tip (or round tip), pipe onto cupcakes, and add final lime zest. You can also use a Ziplock bag with one of the corner tips cut off to use as a makeshift frosting bag.
Frost with tequila-lime buttercream and garnish with lime zest, a sprinkle of coarse sugar, or a pinch of salt for a salted rim effect.
