Step 1: Preheat the oven to 350°F (175°C). Line a 12-cup muffin tin with cupcake liners.
Step 2: In a medium bowl, whisk together the flour, sugar, baking powder, baking soda, and salt. In a large bowl, beat the eggs and softened butter until light and fluffy. Add vanilla extract, sour cream, and buttermilk, and mix until smooth.
Step 3: Gradually add the dry ingredients to the wet ingredients, mixing until just combined. Don’t overmix. Gently fold in the salted caramel sauce, ensuring it's evenly distributed throughout the batter.
Step 4: Fill each cupcake liner about two-thirds full with the batter. Bake for 18–20 minutes, or until a toothpick inserted into the center comes out clean.
Step 5: Let the cupcakes cool in the tin for 5 minutes before transferring them to a wire rack to cool completely.
Step 6: While the cupcakes cool, prepare the frosting. Beat the softened cream cheese and butter together until smooth and creamy.
Step 7: Gradually add powdered sugar, mixing until fluffy. Then, stir in the vanilla extract and salted caramel sauce. Adjust the consistency with a little milk if needed.
Step 8: Once the cupcakes are cool, frost generously with the cream cheese mixture. Drizzle with additional salted caramel sauce and sprinkle a pinch of sea salt on top for an extra burst of flavor.
