Preheat oven to 350°F (175°C). Line a 12-cup muffin pan with liners (or use two pans as needed).
In a large bowl, combine 1 box Betty Crocker Black and White Cupcake mix, 2 eggs, 3/4 cup water, and 1/4 cup vegetable oil. Beat until smooth, following any mixing guidance on the box.
Fill each liner about two-thirds full with batter.
Bake at 350°F for 18–23 minutes, or until a toothpick inserted in the center of a cupcake comes out clean. Remove from oven.
Let cupcakes cool in the pan 5 minutes, then transfer to a wire rack and cool completely before frosting.
Make the frosting: in a bowl, combine the Frosting pouch contents, 2 tsp water, and 1/2 cup softened butter. Beat with a hand mixer or stand mixer until smooth and pipeable.
Fit a piping bag with a Wilton 1M tip (or preferred large star tip), fill the bag with frosting, and pipe swirls onto the cooled cupcakes.
Prepare the Oreos: gently split or break each of the 24 Oreos into halves. Press two Oreo halves into the top of each frosted cupcake to form "Mickey ears," then add sprinkles as desired.