Begin by making the cookie crust. Crush or pulse the Oreo cookies until they are a fine crumb. Then add melted butter and pulse or stir for 30 seconds until well combined. Press into pie plate and chill in the freezer while you make the filling and sauce.
Gently warm the warm milk and whisk in espresso powder until dissolved. Allow to warm on stove over low heat for about 3 minutes.
In a large bowl, combine cream, espresso milk, sugar, vanilla extract and salt. Using a stand or hand mixer, whisk the ingredients for 6-7 minutes until light and fluffy. Spoon mixture into chilled pie crust. Cover and freeze for at least 4 hours or up to a month in advance.
Make the chocolate sauce by combining sugar, cocoa powder, water, vanilla extract and salt over medium low heat until sugar is dissolved and just slightly bubbling around the edges about 3 minutes. Place into glass mason jar and let chill until ready to use. Can make up to a month ahead of time and store in the fridge.
Once ready to enjoy, slice pie and drizzle with chocolate sauce! Top with additional crushed cookies if desired.
Notes
Nutritional values are only an estimate and can vary. Note: The Chocolate Sauce yields about 1 cup but you will only need approximately 1 teaspoon per serving. Enjoy the sauce any other way you'd like!