Preheat the oven to 350°F (175°C). Line a baking sheet with parchment paper.

In a medium bowl, whisk together the flour, cocoa powder, baking soda, and salt until evenly blended.

In a large bowl, beat the softened butter with the granulated and brown sugars until the mixture is light and fluffy — about 2–3 minutes with an electric mixer.

Add the egg and vanilla. Beat until fully combined and smooth.

Gradually add the dry ingredients to the wet mixture. Mix on low speed just until there are no streaks of flour.

Fold in the chocolate chips with a spatula so they’re evenly distributed.

Drop tablespoon-sized scoops of dough onto the prepared baking sheet, spacing them about 2 inches apart.

Bake for 10–12 minutes, or until the edges are set and the centers look slightly soft.

Let the cookies cool on the sheet for 5 minutes, then transfer to a wire rack.

Once fully cool, top each cookie with a spoonful of whipped cream and garnish with chocolate curls just before serving.