Prep. Preheat the oven to 350ºF. Line baking sheet with parchment paper.: As the oven warms, you will notice a faint, dry heat filling the kitchen, which primes the baking surface so cookies start to set the moment they hit the tray. Proper preheating ensures even rise and browning, so I always wait for the full temperature rather than guessing. If your oven runs hot or cool, an oven thermometer will save you from overbaked or underbaked results. A common slip is placing the tray in too early, which can prevent the cookies from spreading correctly.
Cream wet ingredients. In the bowl of a stand mixer fitted with the paddle attachment, cream the 1 cup butter, 3/4 cup brown sugar, and 1/4 cup granulated sugar 1 to 2 minutes, or until smooth and fluffy. Add 1 1/2 teaspoons vanilla and 2 eggs one at a time until combined.: When you cream the butter and sugars , you will see the mixture lighten in color and become aerated, creating tiny bubbles that contribute to lift. The aroma will shift from sweet to a more complex, caramel like scent as the brown sugar blends in. Adding the vanilla introduces warm notes, and incorporating eggs one at a time helps form a glossy emulsion. If the butter is too cold, it will not cream properly, producing dense dough. Scrape the bowl to ensure everything is evenly mixed and avoid overbeating once eggs are added to prevent a cake like structure.
Combine wet and dry ingredients. In a medium bowl, whisk together 2 1/3 cups flour, 3.4 ounce dry pudding mix, 1 teaspoon baking soda, 1 teaspoon baking powder, and 1/4 teaspoon salt. Slowly stir into the wet ingredients until well combined. Fold in the 1 1/2 cups chocolate chips.: The dry mix will smell faintly of vanilla and powdered sweetness, and whisking distributes the leaveners and pudding mix evenly so pockets of rise are consistent. As you slowly incorporate the dry into the creamed base, watch for the dough to come together without streaks of flour. Folding in the chocolate chips last preserves their shape while ensuring even distribution. A frequent mistake is mixing too vigorously, which tightens gluten and yields tougher cookies, so stop mixing the moment the dough is uniform.
Scoop. Using a medium cookie dough scoop, portion the dough onto the baking sheet.: When scooping, you will feel the dough hold shape with a slight tackiness, and the scoops should sit as rounded mounds on the sheet. Spacing is important, I leave room for gentle spread so edges can brown. If the dough is too soft, chill for a bit to prevent excessive flattening. Using a scoop promotes even sized cookies so they bake uniformly, which matters if you want consistent texture across a tray.
Bake. Bake 8 to 10 minutes, or until the edges are lightly golden brown; you want the center to look a little underdone. Let sit 2 to 5 minutes before transferring to a cooling rack. Enjoy with a cold glass of milk!: As the cookies bake, you will notice the edges begin to set first and take on a light golden hue while centers remain pale and soft, that contrast is the cue to pull them. The oven will release a warm, butter rich aroma with chocolate notes as the chips soften. Allowing them to rest a few minutes on the hot sheet lets residual heat finish the center without overbaking, so you end up with a tender inside and slightly crisp rim. A typical error is leaving them in until fully browned, which removes that desirable soft center; remove them when the center still looks slightly underdone for best results.