Preheat your oven to 350°F (convection) and line a baking sheet with parchment paper.

In a stand mixer fitted with a whisk or paddle attachment, beat the room-temperature butter and granulated sugar for 1–2 minutes, until pale and off-white. Mix in the vanilla extract.

Add the all-purpose flour to a heat-safe bowl and microwave for 60 seconds to heat-treat it.

Stir the heat-treated flour, cocoa powder, and crushed Oreos into the butter mixture until a thick brownie-style dough forms. If you prefer a softer filling, mix in 1–2 tablespoons of milk.

Set brownie batter aside.

In a clean bowl, beat the room-temperature butter and granulated sugar for 1–2 minutes, until light and off-white.

Mix in the egg and vanilla extract until fully combined.

Add the all-purpose flour, baking soda, baking powder, sprinkles, and white chocolate. Gently fold or mix on low speed just until a soft cookie dough forms.

Scoop ⅓ cup of cookie dough, flatten it in your palm, and place 1–2 tablespoons of brownie batter in the center.

Wrap the cookie dough around the filling and roll into a ball, sealing completely.

In a small bowl, mix together the granulated sugar and sprinkles. Roll each cookie dough ball in the mixture until fully coated.

Place cookie dough balls onto the prepared baking sheet, leaving space between each cookie.

Bake for 12–13 minutes, until the edges are set and the centers are just soft.

Immediately after baking, use a round bowl, cup, or cookie cutter to gently swirl around each cookie for clean, circular edges.

Let cookies cool on the baking sheet for about 10 minutes before removing.

Enjoy warm for the ultimate gooey center, or store in a chilled environment for up to 8 days.