1 cup (2 sticks) unsalted butter, melted
2/3 cup white granulated sugar
1 cup light brown sugar, packed
2 large eggs, room temp.
2 tsp vanilla extract
2 cups all-purpose flour
2 tsp salt
2 cups semisweet chocolate chips
1. Preheat oven to 350 degrees F. Line 9×13 pan with parchment paper. I spray with cooking spray first to help the parchment stick. Then proceed with two folded pieces of parchment that overextend past the edges of the pan (one lengthwise and one across the width, making a criss-cross). See picture below. I do not add any extra cooking spray or butter. The parchment alone will prevent sticking.
2. In a large bowl, whisk butter and sugars until smooth. Whisk in egg and vanilla.
3. Add flour and salt and stir gently with a spatula to combine. Mix until just moistened (do not overmix). Fold in chocolate chips.
4. Transfer mixture into parchment-lined pan. Spread the batter out evenly across the surface of the pan.
5. Bake for 40-45 minutes until top is golden brown and toothpick inserted into center comes out clean. Allow pan to cool completely. Then use the overhanging parchment to lift out of the pan completely. Place on a cutting board and cut into squares or desired pieces with a sharp knife. Store in an airtight container at room temperature for up to 2 days
Source : allrecipes