In a large Ziploc bag, crush the Oreos into small pieces using a rolling pin or meat mallet.
In the bowl of your electric mixer, combine the sugar, vegetable oil, eggs, and vanilla extract.
Beat on medium speed until the eggs and oil are well incorporated, about 2 minutes. Stop and scrape down the bowl after about 1 minute.
Next, add the yogurt and beat until well combined.
In a separate bowl, combine all the dry ingredients.
Next, add the dry ingredients and milk alternately, beginning and ending with the dry ingredients. Again, stop the mixer and scrape down the sides of the bowl with a spatula.
Fold the crushed Oreos into the cupcake batter.
Pour the batter into a 9×13-inch baking pan.
Bake at 350°F for 26-28 minutes.
Test the cake for doneness by inserting a wooden pick or cake tester into the center of the cake. If the toothpick comes out with dry crumbs or no crumbs, the cake is done.
For this recipe, you don't have to cool the cake before adding the sweetened condensed milk. (If you use pudding, you'll want to cool the cake completely.) Poke holes in the top of the cake and slowly pour the sweetened condensed milk over the cake.
Allow the cake to cool before frosting.
FOR THE FROSTING
Beat butter and cream cheese until smooth, add powdered sugar with the mixer on low.
Stop the mixer and scrape the sides. Add the vanilla and mix until smooth.
Fold in the Cool Whip.
Frost the cooled cake.
Cover and refrigerate until ready to serve.
Store in the refrigerator. it'll be good 4 to 5 days.