Sky High Chocolate Mousse Pie

Name: Sky High Chocolate Mousse Pie
Prep time: 40 min
Cook time: 18 min
Total time: 58 min
Cuisine: American
Ingredients: 18 whole Oreos, crushed into crumbs; 1/4 cup (4 Tablespoons; 60g) unsalted butter, melted; two 4-ounce bars unsweetened chocolate, coarsely chopped (8 ounces total); 2 Tablespoons (30g) unsalted butter; 4 large egg whites*; 1 cup (200g) granulated sugar; 1/4 teaspoon cream of tartar*; 2 cups (480ml) heavy cream/heavy whipping cream; 6 whole Oreos, crushed into crumbs; 1 cup (280ml) heavy cream/heavy whipping cream; 1 Tablespoon (13g) granulated sugar; 1/2 teaspoon pure vanilla extract