In a microwave-safe bowl, microwave butter in 20-second bursts until melted. Add the peanut butter and stir until well combined. Add in the sugars and whisk together. Set aside to cool until just warm.

In a medium bowl, whisk together the flour, baking soda, baking powder, and salt. Set aside.

To the cooled butter mixture, add the eggs, milk, and vanilla and whisk very well until thoroughly combined. Add the flour mixture and stir with a sturdy spatula until combined. Reserving about a quarter of each for topping the dough scoops, stir in the chocolate chips and toffee. The dough will be thick and slightly greasy, don’t worry if not all the mix-ins incorporate perfectly.

Using a large spring-loaded cookie scoop, form the dough into 3-tablespoon rounds. Press reserved chocolate chips and toffee bits firmly onto the tops of each scoop.

For a softer cookie, bake about 12 minutes, or until lightly browned at the edges. For a crispier cookie, bake about 14 minutes, or until lightly golden brown.

Store cookies in an airtight container for up to two days. The longer they sit, the softer they’ll become.