Preheat your oven to 350°F (175°C) and line a large baking sheet with a Silpat baking mat or parchment paper. Set it aside as you begin making the dough.
In a large mixing bowl, whisk together the flour, cornstarch, baking soda, and sea salt until well combined. Set this mixture aside.
In the bowl of a stand mixer, beat the butter, brown sugar, and granulated sugar together until the mixture becomes smooth and creamy, about 2 minutes. Beat in the egg and vanilla extract until fully blended, then gradually add the dry ingredients, mixing just until combined.
Carefully fold in the chocolate chips, making sure they are evenly spread throughout the dough. Take about 2 tablespoons of dough, roll it into a ball, and set it aside. Flatten the dough slightly with your palm and place a piece of caramel in the center. Carefully wrap the dough around the caramel, making sure it is completely enclosed. Repeat with the remaining dough and arrange the cookies 2 inches apart on the prepared baking sheet.
Bake for 10 to 12 minutes, or until the edges turn a light golden brown. Remove the cookies from the oven and immediately sprinkle with flaky sea salt. Allow the cookies to cool on the baking sheet for 5 minutes before moving them to a wire rack to cool completely.
Enjoy these warm, gooey, and perfectly balanced sweet-and-salty cookies!