Pour the cream into a large saucepan and warm over medium heat. Once warm, add the milk chocolate chips, dark chocolate chips, sea salt, and vanilla. Continue to stir until ingredients are fully blended and melted together.

Transfer the chocolate mixture to a bowl, cover with saran wrap, and place in the refrigerator for about an hour (or until the mixture is chilled).

Line the bottom of an 8-inch springform pan with a round of parchment paper. Lightly grease the parchment paper with a small amount of softened butter or oil. Set aside.

Add melted butter and Oreos to a food processor. Blend until the Oreos become a fine crumble. You should be able to press a small amount between your fingers and have it stick together.

Press the Oreo mixture into the bottom of the prepared pan. Firmly press down the mixture to create a solid crust. Set aside.

Once the chocolate mixture is chilled, pour it into a bowl of a standing mixer. With the whisk attachment, blend on medium-high until the chocolate becomes nice and thick. When ready, the mixture will be able to hold its shape. Don’t over-whip this.

Carefully spoon the chocolate mousse on top of the Oreo mixture. Spread it out evenly with a rubber spatula or offset spatula.