Preheat your oven to 350°F (175°C) and line a baking tray with parchment paper.
Cream butter with brown sugar and granulated sugar until light and fluffy.
Mix in yogurt (or applesauce) and vanilla extract until smooth.
In a separate bowl, whisk together flour, baking soda, and salt. Gradually fold into wet ingredients.
Stir in chocolate chips evenly.
Scoop tablespoons of dough onto the tray, leaving space for spreading.
Bake for 10–12 minutes until edges turn golden but centers remain soft.
Cool on the tray for 5 minutes, then transfer to a wire rack. Cookies firm up as they cool; a little gooey center is perfect.