Pull butter out about an hour before using to get it to room temperature. Don’t melt the butter in these cookies—it will cause greasy and flat cookies. Line baking sheet(s) with parchment paper or a silicone baking mat.
In a large bowl, add the room temperature butter, brown sugar, and granulated sugar. Cream together until light and fluffy, about 2–3 minutes. Once incorporated, stop mixing; you don’t want to beat too much air in. Add in vanilla and 1 egg. Mix until incorporated. Add in the other egg and mix again until incorporated.
In a different bowl, add in the flour, dry pudding mix, baking powder, baking soda, and salt. Mix to combine.
Add the dry ingredients to the wet ingredients and mix until just combined. Add in the toffee bits and chocolate chips. Fold these ingredients into the dough. Cover the dough tightly and place in the fridge for 20–30 minutes. This allows the pudding time to firm up the dough. Preheat oven to 350°F.
Roll the cookie dough into large balls, about 2 tablespoons each, shaping them taller rather than wider. If the dough becomes too warm while rolling, freeze the balls for 5–10 minutes to firm them up. If the dough feels wet and soft, it may spread too much and flatten while baking.
Add cookie dough balls to the prepared and lined baking sheet, about 6–8 cookies at a time. They spread a lot while baking and need ample room! Bake for 9–12 minutes or until edges are lightly golden brown. Be careful not to overbake as they firm up while cooling.
Remove tray from the oven and press a few more chocolate chips into the tops of the cookies within 1–2 minutes of pulling them out. This ensures even placement of chocolate and also makes them look pretty. Allow cookies to cool on the baking tray for 5 minutes before transferring them to a cooling rack. Repeat, baking the remaining dough balls until all the cookies are baked.
Notes
Note 1: Use instant pudding mix instead of cook-and-serve pudding mix. Make sure the pudding mix is not sugar-free or reduced-calorie, as these varieties won't yield the same results. Pay attention to the box size; you need the 3.4-ounce box. When incorporating the pudding mix into the cookies, use it in its dry form—do not prepare it according to the package directions.Storage: These cookies will stay good for a week, but they're best in the first 2 days. Let them cool completely, then place in an airtight container at room temperature. To freeze the dough, freeze cookie dough balls on a sheet pan until solid, then transfer them to an airtight container or bag, separated by parchment paper to prevent sticking. You can freeze for up to 3 months and bake without thawing, just add 2 minutes to the bake time.