3/4 cup (6 oz.) unsalted butter, chilled and cut into cubes
5 tablespoons unsalted butter, softened
3 large eggs
1 large egg yolk
2 teaspoons lemon zest plus 2/3 cup fresh juice (from about 6 lemons)
5 large eggs whites
How to Make It
Preheat oven to 350°F. Lightly grease 6 (4-inch) round tart pans with removable rims, and place on a large rimmed baking sheet. Process matzos, almonds, and 1/2 cup of the sugar in a food processor until finely ground, about 1 minute. Add cubed chilled butter; pulse until mixture resembles coarse meal, 6 to 8 times. Evenly divide matzo mixture among tart pans; press onto bottom and up sides of pans. Bake in preheated oven until crusts are lightly browned, 14 to 16 minutes. Transfer pans to a wire rack; cool completely, about 30 minutes. Remove crusts from pans.
Beat softened butter and 1 1/4 cups of the sugar with an electric mixer on medium speed until blended, about 1 minute. Add whole eggs and egg yolk, 1 at a time, beating just until blended after each addition. Gradually add lemon juice, beating on low speed just until blended. Stir in zest. Transfer mixture to a medium saucepan. Cook over medium-low, whisking constantly, until mixture thickens and coats the back of a spoon, 14 to 16 minutes. Transfer mixture to a medium heatproof bowl; cover with plastic wrap, pressing directly onto the surface to prevent a film from forming. Chill at least 4 hours.
Combine egg whites and remaining 1 1/2 cups sugar in a medium saucepan. Cook over medium-low, whisking constantly, just until sugar melts and mixture is smooth, about 5 minutes. Transfer mixture to the bowl of a heavy-duty electric stand mixer fitted with the whisk attachment. Beat on low speed 5 minutes. Increase speed to medium-high, and beat until mixture is shiny and stiff peaks form, about 6 minutes.
Evenly divide chilled lemon curd among tart shells. Top evenly with meringue. Using a kitchen torch, toast meringue until golden brown.