Preheat the oven to 350°F (175°C) and line baking sheets with parchment paper.

In a bowl, cream the softened butter with brown and granulated sugar until light and fluffy, about 2–3 minutes.

Beat in the egg and vanilla extract until smooth; the batter should look glossy.

In another bowl, whisk together cake flour, bread flour, baking soda, and salt.

Gradually add the dry mix to the wet mix, stirring until just combined; don’t overwork the dough, it should be slightly sticky.

Fold in the chocolate chips with a spatula until evenly distributed.

Cover and chill the dough for at least 30 minutes.

Scoop tablespoon-sized mounds of dough onto the prepared baking sheet, spaced about 2 inches apart.

Bake for 10–12 minutes, until the edges are golden and the centers still look a touch soft.

Let cookies cool on the baking sheet for 3–5 minutes before transferring to a wire rack to finish cooling.