Preheat your oven to 350°F (175°C). Line a 12-cup muffin tin with cupcake liners. This helps the cupcakes bake evenly and makes serving much easier.

Add flour, baking powder, and salt to a medium bowl. Whisk everything together until evenly combined. Set the bowl aside while you prepare the wet ingredients.

Place softened butter, brown sugar, and granulated sugar in a large bowl. Beat until light and fluffy. This usually takes about two to three minutes with an electric mixer.

Add the eggs one at a time. Beat well after each addition. Mix in the vanilla extract until the mixture looks smooth and creamy.

Add the dry ingredients in two batches. Alternate with the buttermilk and cream soda. Mix gently after each addition. Avoid overmixing, as it can make your cupcakes dense.

Fold the caramel sauce into the batter using a rubber spatula. Mix gently until the caramel is evenly distributed. The batter should look smooth and smell wonderfully sweet.

Divide the batter evenly between the prepared cupcake liners. Fill each liner about two-thirds full. This leaves enough space for the cupcakes to rise without overflowing.

Bake for 18 to 20 minutes. Check them with a toothpick near the center. The cupcakes are ready when the toothpick comes out clean or with a few crumbs.

Remove the cupcakes from the tin after a few minutes. Transfer them to a wire rack. Let them cool completely before adding frosting, or the buttercream may melt.

Beat the softened butter until creamy. Gradually add powdered sugar and mix until fluffy. Add caramel sauce, vanilla, cream, and salt. Beat again until smooth and spreadable.

Transfer the buttercream into a piping bag fitted with a star tip. Pipe a generous swirl onto each cooled cupcake. Keep the pressure steady for an even and pretty finish.

Mix the caramel sauce with cream soda. Drizzle a small amount over each cupcake. Add a few butterscotch chips if desired. Serve these magical cupcakes fresh and enjoy.