Preheat your oven to 350°F (175°C) and prepare your cupcake tins by placing liners in each cavity.
In a large mixing bowl, combine the plain all-purpose flour, caster sugar, baking powder, and fine salt.
Add the softened unsalted butter into the dry mix and continue mixing on medium speed until the mixture resembles coarse crumbs.
Incorporate the large eggs, whole milk, vegetable oil, Greek yogurt, tequila (if using), and vanilla extract into the bowl. Mix until everything is combined and the batter is smooth.
Divide the batter into two bowls. In one bowl, add pink/red food gel and strawberry flavoring, while in the other bowl, mix in yellow food gel and mango flavoring.
Transfer each colored batter into separate piping bags. Pipe the yellow batter into each cupcake liner, followed by a swirl of the red batter on top.
Bake your cupcakes for about 18-20 minutes, or until a toothpick comes out clean.
Once baked, let the cupcakes cool in the tins for about 5 minutes, then transfer them onto a wire rack to cool completely.
Prepare the frosting by mixing American buttercream or Swiss meringue buttercream with the pink/red food gel, strawberry flavoring, yellow food gel, and mango flavoring until light and fluffy.
Lightly brush the tops of each cooled cupcake with water, then dip them into granulated sugar.
Using an open star piping tip, frost each cupcake with the vibrant buttercream.
Adorn each frosted cupcake with two lime wedges and a halved strawberry on top.