1-First step: Make the crust dough Start by blending the flour, granulated sugar, and slivered almonds in a food processor until the nuts are finely ground. Add the chilled butter and pulse until the mixture looks like coarse meal. Then blend in the lightly beaten egg just until the dough comes together. The dough should feel soft but manageable, which is why this tart is easier to shape than many traditional pies. Flatten the dough into a square, wrap it tightly, and chill it for 1 hour. This chilling time helps the crust bake up tender and keeps the butter cold, which is important for texture. If you prefer a different nut flavor, pistachios, walnuts, or pecans can be used instead of almonds.

2-Second step: Shape and blind bake the crust Line a 10-inch removable-bottom tart pan with parchment paper. Cut the chilled dough into 1-inch slices, then press the slices into the bottom and up the fluted edges of the pan. This slicing method is especially handy because it avoids rolling out a soft dough, which can be tricky for beginners. Refrigerate the shaped crust for 1 hour. Then bake it at 375°F for about 17 minutes, or until golden brown. If the crust puffs during baking, gently press it down while it is still warm. Cool it completely, remove the pan ring, and transfer the crust to a serving plate.

3-Third step: Cook the lemon cream filling In a heatproof bowl, whisk the granulated sugar and lemon zest together until the mixture smells fragrant. This little step wakes up the citrus oils and gives the filling a brighter flavor. Next, whisk in the eggs and lemon juice until smooth. Set the bowl over a double boiler and cook the mixture, whisking constantly, until it reaches 180°F and thickens. A thermometer helps a lot here because the filling is delicate. If it gets too hot, the eggs can scramble, so keep the heat gentle and steady. Strain the filling to remove any bits of cooked egg, then blend in the softened butter a few pieces at a time until the mixture turns light and fluffy. Chill the lemon cream for at least 4 hours or overnight. Before using, whisk it briefly to bring back a smooth, spreadable texture.

4-Fourth step: Prepare the Swiss meringue Combine the egg whites, sugar, and cream of tartar in a bowl set over simmering water. Stir gently while heating until the sugar dissolves and the mixture reaches 175°F. This creates the base for a stable Swiss meringue, which is glossy and holds its shape well. Transfer the mixture to a stand mixer and whip until stiff, shiny peaks form. The meringue should look thick, smooth, and airy. If you prefer, Italian meringue can be used instead, but Swiss meringue is wonderfully simple once you get the temperature right.

5-Fifth step: Assemble the tart Spoon or pipe the chilled lemon cream into the cooled crust and smooth the top. Then pile on the meringue, making sure to spread it all the way to the edges so it seals the filling beneath it. This helps keep the meringue from shrinking away from the crust. For a polished look, use the back of a spoon to create soft swoops and peaks. A tart like this does not need perfect decoration to look lovely. Its natural layers already do most of the work.

6-Final step: Brown, chill, and serve Lightly brown the meringue with a kitchen torch, or place the tart in a 350°F oven for a short time until the top is lightly golden. After that, chill the tart for at least 1 hour before serving. This final chill helps the slices hold their shape and keeps the texture balanced. Just before serving, dust the top with confectioners’ sugar. The tart is best served cold, especially if you want clean slices and the smoothest bite. For a closer look at smart baking methods, you may find our baking basics guide for home cooks helpful when working with custards, crusts, and meringues.