Preheat the oven to 350°F / 175°C. Grease a 12-inch pizza pan or line a baking sheet with parchment paper.
In a small bowl, whisk together the flour, baking soda, and salt. Set aside.
In a large mixing bowl, beat the softened butter, brown sugar, and granulated sugar until light and fluffy.
Add the egg and vanilla extract. Mix until smooth and well combined.
Gradually add the dry ingredients to the butter mixture. Mix just until a soft cookie dough forms.
Fold in the chocolate chips.
Press the dough evenly into the prepared pizza pan, leaving a little space around the edges because the cookie will spread as it bakes.
Bake for 20 minutes, or until the edges are golden and the center is just set. Do not overbake, as the cookie will continue to firm up while cooling.
Let the cookie pizza cool for about 10 minutes before adding toppings.
Add vanilla ice cream, caramel sauce, chocolate sauce, sprinkles, whipped cream, or crushed nuts.
Slice into wedges and serve like pizza.
