To make the crust:
Combine the flour, sugar and salt in a large bowl or the bowl of a food processor.
Add the cubed butter and cut into the other ingredients with a pastry blender until coarse and sandy, or if you're using a food processor, pulse in short bursts.
Whisk together the egg yolk and 2 tablespoons of the ice water. Add to the flour mixture and use a spoon or your hands (or a few pulses) to bring it together into large chunks. If needed, add more ice water ½ tablespoon at a time. (Don't add too much water, the dough won't completely come together in a ball if you're using a food processor, and that's okay.)
Dump it out on your counter and form dough into a disk. Cover with plastic wrap and chill in the fridge 1 hour. (Can be made up to 3 days ahead.)
On a floured surface, roll the crust out to a rough 12 or 13-inch circle. Transfer to a greased 8-inch tart pan and press it in gently. Remove any overhanging crust, you can cut it off with a knife or fold it under.
Freeze for 30 minutes while you preheat the oven to 400°F.
Line chilled crust with greased foil or parchment paper and fill tart with baking weights, dry rice, or beans. Bake for 18-20 minutes until set. Remove foil and weights and bake for 5-8 minutes more, until it appears dry and lightly golden brown. Cool completely.
For the filling:
Warm the milk in a medium saucepan over medium heat just until bubbles appear at the edges. Do not bring to a boil.
Meanwhile, whisk together the egg yolks, sugar, cornstarch, and lemon zest. Mixture will be very thick. When milk is warm, add to the egg mixture in a small steady stream while whisking constantly.
Return mixture to the saucepan and cook over medium heat until thick, while stirring constantly with a rubber spatula. This should take about 3-4 minutes.
Remove from heat and stir in butter, lemon juice, and vanilla extract.
Pour into a bowl and cover with plastic wrap, pressing it directly on the surface of the custard. Chill completely, 1-2 hours.
To assemble tart:
Stir cooled custard until smooth and spread into the tart crust.
Top tart with fresh berries. Serve immediately, or chill in the fridge for up to 2 hours. Tart is best the day it is assembled, but can be stored in the fridge for a few days.
- Make it easy and use a tart pan with a removeable bottom!
- Crust can be made in advance. Store crust dough in the fridge for up to 3 days and in the freezer for up to 1 month. Store baked (unfilled) tart shell at room temperature, covered with plastic wrap, for up to 3 days.
- Prepare the filling at any time while the crust dough is chilling or being baked, and up to 1 week in advance.
- If you don't have a tart pan, you can bake this in a shallow 9-inch pie pan. The filling will be thinner, but it should work. Follow the same par-baking instructions as outlined in the recipe, and serve the tart straight from the pan.
Calories: 400kcal, Carbohydrates: 43g, Protein: 7g, Fat: 23g, Saturated Fat: 13g, Cholesterol: 198mg, Sodium: 109mg, Potassium: 189mg, Fiber: 2g, Sugar: 21g, Vitamin A: 825IU, Vitamin C: 28mg, Calcium: 104mg, Iron: 2mg