Fill a large bowl with ice water and set aside.
Place yolks, sugar, cornstarch, milk, and salt in a medium saucepan and whisk until smooth and well combined. Cook over medium heat, whisking constantly until pastry cream begins to thicken, about 5 minutes. Once the mixture thickens, whisk until you see bubbles, then continue to cook and whisk for 1 minute or until an instant-read thermometer registers 180°F. Remove from heat and stir in white chocolate chips, butter, and vanilla. Whisk until the chocolate and butter are fully melted. Strain mixture through a fine-mesh sieve into a medium bowl. Set bowl onto ice bath to stop the cooking and prevent curdling. Cover the surface with plastic; refrigerate until well chilled, at least 2 hours or overnight.
Combine 6 tablespoons melted butter, milk, eggs, vanilla, flour, cocoa powder, sugar and salt in a blender. Blend on high speed until smooth and well combined, about 30 seconds. Blend in enough red food coloring to make a deep red batter. Refrigerate at least 1 hour.
Heat an 8-inch or 9-inch nonstick pan over medium heat. Use a pastry brush or paper towel to coat the pan with a thin layer of remaining melted butter. Ladle in a scant 1/4 cup of batter and quickly swirl the pan to cover the bottom with a thin layer of batter. Cook for about 1 minute, or until the edges begin to look dry and lighten in color. Run a rubber spatula around the edge to loosen, then carefully flip the crêpe. Cook another 20- 30 seconds. Transfer to a plate to cool.
Repeat until all of the batter has been used, buttering the pan each time. You should have about 30 crêpes (you’ll need 25). Cover loosely and let crêpes cool to room temperature.
To assemble cake, place one crêpe on the center of your serving plate. Spread 2 tablespoons of pastry cream evenly on top. Repeat layering crêpes and filling until you’ve used 24 crêpes (go higher if you’d like). Top with the final crêpe and refrigerate for at least 4 hours and up to 1 day.
When ready to serve, top with whipped cream and fresh raspberries.
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