PREP: Preheat the oven to 325 degrees F. Lightly grease a 9-inch tart or pie pan with cooking spray. In a powerful blender or food processor, add the whole Oreo cookies and blend/pulse until the cookies are crumbs. Measure out 1 level cup of crumbs. Melt the butter in the microwave and allow it to slightly cool.
CRUST: In a medium-sized bowl, combine cookie crumbs and sugar, and then add melted (but not hot) butter. Stir until well combined. Press crust firmly into the bottom of the greased and prepared pan and 3/4 the way up the sides. Bake for 10 minutes and then remove to a wire rack and cool completely.
FUDGE FILLING: Whisk together cream and egg yolks in a small saucepan. Heat over medium-low heat, stirring constantly, until mixture is hot (but NEVER boils) and thickens slightly. (If you run your finger along the back of a wooden spoon, it should leave a well defined track mark). Remove the mixture from the heat and stir in the chocolate chips until completely melted and mixture is smooth. Mix in the salt and vanilla extract.
CHILL: Pour the fudge filling mixture into the prepared crust and spread into an even layer with the back of a spoon. Cover with plastic wrap (See Note 2) and then refrigerate for at least 3 hours up to overnight.
GANACHE: Add the heavy whipping cream, milk chocolate chips, and light corn syrup to a microwave safe bowl. Microwave in bursts of 15 seconds, stirring in between each burst for 15 seconds, until melted and smooth. Smooth this glaze evenly over the tart and chill for 1 more hour before serving.
SERVING: Using a sharp and hot knife (run the knife under hot water, dry it off, and make a cut, then repeat) cut tart into thin slices. Serve, if desired, garnished with miniature chocolate chips, Oreo crumbs, or a sprinkle of powdered sugar. Return any leftovers, covered tightly, to the fridge. Refrigerate up to 5 days. Tart does not freeze/thaw well.