In a mixing bowl, whisk together the egg yolk, heavy cream, and vanilla extract. In a food processor, combine the flour, icing sugar, and salt, then pulse in the chilled butter until the mixture resembles coarse crumbs. Gradually add the egg mixture, blending until just combined. Wrap the dough in plastic and chill for 1 hour until firm.

Preheat your oven to 375°F (190°C). Roll the chilled dough on a floured surface into an 11-inch circle, then gently place it into a tart pan, pressing to fit snugly. Freeze for 30 minutes, then line with parchment paper and fill with pie weights. Blind bake for 30 minutes until golden brown. Cool slightly and lower the oven temperature to 350°F (175°C).

In a medium saucepan over medium-low heat, combine the lemon zest, lemon juice, whole egg, egg yolks, honey, and salt, stirring continuously until the mixture thickens and reaches 165°F (74°C). Once thickened, remove from heat, blend in the chilled butter, and strain through a fine mesh sieve for smoothness. Add heavy cream and stir until well mixed.

Pour the prepared lemon curd into the cooled crust, smoothing the top with a spatula. Bake in the oven at 350°F (175°C) for 10-12 minutes, just until the filling is set but still slightly jiggles in the center. Allow to cool to room temperature as you prepare the raspberry topping.

In a blender, puree the fresh raspberries and strain through a fine mesh sieve to remove seeds. Combine this raspberry puree with honey, salt, and lemon juice in a saucepan. In a separate small bowl, mix the cornstarch with water to create a slurry, then whisk it into the raspberry mixture. Simmer on medium heat until it thickens and reaches 170°F (77°C), then cool slightly.

Pour the thickened raspberry topping over the cooled lemon curd layer in the tart. Spread it evenly, then cover the tart with plastic wrap and refrigerate for at least 2 hours to set perfectly. This chilling time enhances the flavors and allows for easy slicing later.

Once set, carefully remove the tart from the pan and slice into wedges. Serve the Classic Lemon Raspberry Tart chilled or at room temperature, optionally garnished with additional fresh raspberries for a delightful presentation. Enjoy the refreshing flavors of this lovely dessert!