Preheat the oven to 350°F (175°C). Line two baking sheets with parchment paper.
Whisk the all-purpose flour, baking soda, and fine sea salt together in a medium bowl.
Combine the melted butter, granulated sugar, light brown sugar, and light corn syrup in a large bowl. Beat vigorously with a spatula until the mixture is uniform.
Add the egg, milk, and vanilla extract to the butter mixture. Beat vigorously again until smooth.
Stir the dry ingredients into the wet ingredients gradually until just combined. Fold in the semisweet chocolate chips gently. The dough will be loose and sticky.
Scoop 1 1/2-tablespoon portions of dough onto the lined baking sheets. Space the dough balls at least 2 1/2 inches apart to allow for spreading.
Bake one sheet at a time for 12 minutes, rotating the pan halfway through. The cookies are done when they are flat and golden brown. For food safety, baked goods containing eggs should reach an internal temperature of 160°F (71°C).
Remove the baking sheet from the oven and tap it firmly against the counter to deflate the cookies.
Cool the cookies on the baking sheet for 5 minutes before transferring them to a wire rack to cool completely.