Blend: Be sure your ice cream is fully frozen before starting. Press ice cream to the bottom of a heavy duty blender. Blend a few seconds, scraping sides down if needed; blend just until ice cream is creamy and smooth, but don't overdo it.
Pulse: Press Oreo cookies into the ice cream; add vanilla extract. Pulse a few times until crumbs are mixed in, to your liking.
Serve: Divide into individual glasses and serve immediately. Garnish with additional cookies, if desired.
Notes
Much of the blending time will have to be done by eye, as every blender and ice cream brand is different. Take care not to over-blend. Feel free to switch up your add-ins. Try M&M's, frozen blueberries or strawberries, frozen cookie dough, or leftover brownies.As for a heavy duty blender, This Ninja is what I've used for years to make Blizzards and smoothies.