Preheat the oven to 180°C (160°C fan) / 350°F and line a muffin tin with paper cupcake cases.

In a mixing bowl, sift together the flour, cocoa powder, baking soda, baking powder, and salt. Whisk to combine and set aside.

In a separate bowl, or in the bowl of a stand mixer, combine the melted butter with both the granulated and brown sugars. Beat until the mixture is smooth. Add the eggs one at a time, beating well after each addition and scraping down the sides of the bowl to ensure everything is incorporated. Add the vanilla extract and mix until combined.

Begin incorporating the dry ingredients by adding one-third of the flour mixture to the wet ingredients. Gently stir until just combined. Then add half of the buttermilk and mix gently again. Repeat this process, alternating between the remaining flour mixture and buttermilk, ending with the flour. Be careful not to overmix—the batter should be just combined to avoid dense or tough cupcakes.

Spoon the batter into the prepared cupcake cases, filling each about two-thirds full. Bake in the preheated oven for approximately 18–23 minutes, rotating the pan halfway through baking to ensure even cooking. The cupcakes are done when a skewer inserted into the center comes out with just a few moist crumbs.

Allow the cupcakes to cool in the tin for 5 minutes, then transfer them to a wire rack to cool completely.

Place the unwrapped caramels and cream in a small saucepan over low heat. Stir continuously until the caramels are completely melted and the mixture is smooth and glossy. Add the sea salt flakes, if using, and stir through. Set aside to cool before using.

In a large mixing bowl, beat the softened butter and brown sugar together until the mixture becomes light and fluffy—this should take about 4–5 minutes. Scrape down the sides of the bowl as needed during mixing to ensure the sugar is evenly distributed and begins to dissolve.

Add ½ cup (125ml) of the cooled caramel sauce to the butter mixture, along with the vanilla extract and salt if using. Beat until well combined.

With the mixer on low speed, gradually add the icing sugar in batches—add about one-quarter at a time, reserving the final ½ cup and only adding it if needed to reach your desired frosting consistency. Once incorporated, increase the speed to medium-high and beat for an additional 2 minutes, scraping down the sides of the bowl as necessary.

Finally, add the cream and beat for another 30–40 seconds until the frosting is smooth and fluffy.

Using a cupcake corer or small paring knife, cut a small well in the center of each cooled cupcake. Fill each cavity with 1–2 teaspoons of caramel sauce. If desired, you can top the filled hole with a small piece of the removed cupcake, but this step is optional.

Pipe the caramel buttercream generously onto the tops of each cupcake.

Finish with a drizzle of the remaining caramel sauce and a touch of melted chocolate for an extra-decadent finish.

If you try this recipe, please consider leaving a comment and rating—it means a lot and helps others discover it too!