01 - In a food processor, pulse flour, powdered sugar, and salt. Add cold cubed butter and pulse until mixture resembles coarse crumbs. Add egg yolk and 1 tbsp cold water, pulsing until dough begins to come together. Add more water if necessary. Gather dough, flatten into a disk, wrap in plastic, and refrigerate for 30 minutes.
02 - Preheat oven to 350°F. Roll out chilled dough and press into six 4-inch tart pans, pressing gently into the edges. Prick the bases with a fork to prevent bubbling. Line each shell with parchment paper and fill with pie weights or dried beans. Bake for 12 minutes. Remove weights and parchment, then continue baking for 8-10 minutes until golden brown. Let cool completely in pans.
03 - Combine milk, heavy cream, and honey in a saucepan. Heat over medium heat until just simmering, stirring occasionally. Meanwhile, whisk together egg yolks, cornstarch, vanilla extract, and salt in a heat-proof bowl. Gradually whisk about half of the hot milk mixture into the yolks to temper them, then pour the yolk mixture back into the saucepan.
04 - Cook the custard over medium heat, stirring constantly with a wooden spoon or heat-proof spatula, until mixture thickens and coats the back of the spoon, about 3-4 minutes. Do not let it boil. Transfer to a clean bowl, press plastic wrap directly onto the surface to prevent a skin from forming, and cool to room temperature.
05 - Whisk together whole eggs, egg yolks, sugar, lemon juice, and lemon zest in a saucepan. Cook over medium-low heat, stirring continuously, until mixture thickens enough to coat the back of a spoon, 5-7 minutes. Do not let it boil or the eggs may scramble. Remove from heat.
06 - Immediately whisk cubed butter into the hot lemon mixture until completely melted and smooth. Pour curd into a clean bowl and press plastic wrap directly onto the surface. Refrigerate until set and completely cooled, about 1 hour.
07 - Spoon or pipe the cooled honey custard into the tart shells, filling each about three-quarters full. Smooth the tops with an offset spatula. Carefully spread a layer of chilled lemon curd over the custard layer. Arrange fresh strawberry slices on top in an attractive pattern. Garnish with fresh mint leaves if desired. Serve chilled or refrigerate until ready to serve.