Step 1

Preheat oven to 350°F with a rack in center. Beat butter with both sugars, baking powder, baking soda, and salt on medium-high speed until light and creamy, about 2 minutes. Add eggs, one at a time, beating to combine after each addition.

Step 2

Beat in vanilla. Add flour and beat on low to combine. Beat in cereal, chocolate, pretzels, and toffee bits to combine, a few seconds.

Step 3

Scoop 1/4-cup balls of dough onto parchment-lined baking sheets, spaced 2 inches apart. Flatten each slightly. Press pieces of chocolate and pretzel and a few cereal flakes on top of each cookie.

Step 4

Bake 8 minutes, then remove from oven and bang sheets on counter or stove top. Return to oven and bake until cookies are barely set in centers and starting to brown on edges, 8 to 9 minutes more. Let cool on sheets 5 minutes, then transfer to wire racks and let cool completely. Store in an airtight container at room temperature up to 3 days, or freeze up to 1 month.