Preheat the oven to 350°F (175°C) and line a 12-cup muffin tin with cupcake liners.

In a medium bowl, whisk together the flour, baking powder, baking soda, and salt.

In a large bowl, beat the softened butter, cream cheese, and granulated sugar together until light and fluffy.

Add the eggs one at a time, beating well after each addition, followed by mixing in the vanilla extract.

Gradually add the dry mixture to the wet mix, alternating with the milk, starting and ending with dry ingredients.

Mix until just combined to avoid over-mixing; the batter should be smooth and creamy.

Spoon the batter into the cupcake liners, filling each about two-thirds full.

Bake for 18-22 minutes or until a toothpick inserted in the center comes out clean.

Remove from the oven and allow the cupcakes to cool completely on a wire rack.

In a saucepan over medium heat, melt the brown sugar, butter, and heavy cream, stirring continuously until thickened (around 3-5 minutes).

Remove from heat and stir in the vanilla extract and sea salt. Allow the caramel to cool slightly.

Once the cupcakes are cool, use a cupcake corer or a small knife to cut a hole in the center of each cupcake.

Fill this hole with the delicious salted caramel sauce.

For the frosting, beat together the cream cheese, butter, powdered sugar, salted caramel sauce, and vanilla extract until smooth.

Generously frost each cupcake with the frosting.

Drizzle extra salted caramel sauce over the frosting and finish with a pinch of sea salt.