Beat together the butter, light brown sugar, and corn syrup until lightened in colour and fluffy. Beat in the vanilla extract, baking powder, kosher salt, and baking soda until even, then beat in the egg until completely even and combined. Beat in the flour, then stir in the chocolate chunks and caramel bits. Cover the bowl and refrigerate for 1 to 2 hours.

Preheat the oven to 325°F. Scoop rounded tablespoonsful of the chilled dough onto parchment or silpat lined baking sheets. Be sure to leave three inches or so of space between the cookies to allow them to spread. Sprinkle the tops lightly with the coarse sea salt flakes.

Bake for 14-18 minutes, or until the edge are set and golden brown. They will still look underdone in the center, but the edges should be firm. If you want them to stay chewy, be sure to pull them before they're completely set in the middle.

Let the cookies cool for at least 5 minutes on the parchment or silpat before using a flexible, thin spatula to lift them and transfer them to a wire rack to completely cool. Store in an airtight container at room temperature.