Preheat your oven to 375°F (190°C). Grease your donut pan thoroughly with butter or cooking spray.

In a large bowl, whisk together the flour, sugar, baking powder, and salt.

In a separate bowl, whisk together the milk, eggs, melted butter, and vanilla extract.

Pour the wet ingredients into the dry ingredients and stir gently until just combined. Don't overmix.

Fold in the crushed Oreos, leaving some chunks visible.

Transfer the batter into a piping bag or a ziplock bag with the corner cut off.

Pipe the batter into the donut pan, filling each cavity about two-thirds full.

Bake in the preheated oven for 10-12 minutes, or until a toothpick comes out clean.

Let the donuts cool in the pan for 5 minutes before moving them to a cooling rack.

In a medium bowl, whisk together the powdered sugar, milk, melted butter, and vanilla extract until thick but pourable.

Stir in the finely crushed Oreos.

Once the donuts are cool, dip the top of each donut into the glaze and let the excess drip off.

Add a half Oreo on top of each glazed donut and sprinkle with extra crushed Oreos.