Keto Torta della Nonna — Traditional Italian Custard Tart

Torta della Nonna, which translates roughly to “Grandmother’s Cake,” is a beloved Italian dessert built around a wonderfully simple combination: tender sweet pastry, silky lemon-vanilla custard, crunchy pine nuts, and a delicate coating of powdered sugar. Although the name suggests a rustic family dessert, a well-made Torta della Nonna has an elegant balance of textures and flavors. This detailed version is designed as a homemade celebration cake. The pastry is buttery and tender, the custard is thick enough to slice cleanly while remaining creamy, and the pine nuts provide a subtle nutty contrast. A thin layer of fruit jam can also be included for extra sweetness and depth.

Ingredients

• 3 cups all-purpose flour (about 375 g)
• 1 cup cold unsalted butter, cubed (about 225 g)
• 1 cup granulated sugar (about 200 g)
• 2 large eggs
• 1 egg yolk
• 1 teaspoon vanilla extract
• Finely grated zest of 1 lemon
• 1 teaspoon baking powder
• 1 small pinch of salt
• 4 cups whole milk (about 1 liter)
• 6 large egg yolks
• 1 cup granulated sugar (about 200 g)
• 1/2 cup cornstarch (about 60 g)
• 1 tablespoon vanilla extract, or seeds from 1 vanilla bean
• Finely grated zest of 1 lemon
• Optional: 3/4 cup (240 g) apricot, raspberry, strawberry, or fig jam
• 1/4 cup pine nuts
• Powdered sugar, as needed

Instructions

1. Combine the flour, sugar, baking powder, salt, and lemon zest in a large bowl and stir until evenly distributed.
2. Add the cold butter cubes and work into the flour mixture using fingertips or a pastry cutter until it resembles coarse crumbs.
3. Add the eggs, egg yolk, and vanilla. Mix gently until a soft dough forms.
4. Transfer the dough to a lightly floured work surface and knead briefly.
5. Divide the dough into two pieces (one slightly larger), flatten into disks, wrap separately, and refrigerate for at least 1 hour.
6. Pour milk into a saucepan, add lemon zest and vanilla, and heat gently until hot and steaming but not boiling.
7. Remove from heat and let stand for several minutes to infuse.
8. In a separate bowl, whisk egg yolks and sugar until smooth and slightly lighter in color.
9. Gradually add cornstarch while whisking continuously until no lumps remain.
10. Slowly pour some of the warm milk into the egg mixture while whisking constantly until approximately half the milk is incorporated.
11. Pour the tempered egg mixture back into the saucepan with the remaining milk.
12. Place the saucepan over medium-low heat and whisk continuously, scraping the bottom and corners.
13. Cook until the mixture thickens, then continue cooking for another minute or two until it holds soft peaks.
14. Pass the hot custard through a fine sieve if necessary.
15. Transfer the custard to a clean bowl and press plastic wrap directly against the surface to prevent a skin from forming.
16. Cool the custard until no longer hot, then refrigerate for approximately 30 minutes.
17. Roll the larger pastry disk into a circle approximately 12 inches wide and 1/4 inch thick.
18. Transfer the pastry to a lightly buttered 9-inch tart pan, pressing gently into the bottom and sides without stretching.
19. Trim away excess pastry around the rim.
20. If using jam, spread a thin, even layer over the bottom of the pastry.
21. Spoon the chilled custard over the jam and spread into an even layer, leaving room for the top pastry.
22. Roll the second dough disk large enough to cover the tart and place it over the custard.
23. Press the edges together to seal, trim excess dough, and make several small openings in the top for steam.
24. Scatter pine nuts evenly over the pastry and press lightly into the surface.
25. Preheat the oven to 350°F (175°C).
26. Bake the tart for approximately 45–55 minutes until the pastry is deeply golden and fragrant.
27. If the surface browns too quickly, loosely cover with aluminum foil.
28. Remove from the oven and cool at room temperature for about an hour.
29. Refrigerate for approximately two additional hours to allow the custard to set.
30. Remove from the pan and dust generously with powdered sugar before serving.

Notes

Yield: 1 large 9-inch tart. Servings: 10–12. Preparation: 30 minutes. Pastry chilling: 1 hour. Custard preparation: 20 minutes. Custard cooling: 30 minutes. Assembly: 20 minutes. Baking: 45–55 minutes. Final cooling: About 3 hours. Store the finished tart covered in the refrigerator for up to 4 days. Individual slices can be frozen for up to approximately 2 months. For the best texture, allow individual slices to sit at room temperature for a short time before serving.