Start your pastry dough by combining flour and granulated sugar in a bowl. Cut softened butter into small pieces and mix until it looks like coarse breadcrumbs. Add your egg and vanilla bean paste, then stir until the dough just comes together—don't overmix or your tart crust gets tough instead of tender.
Press the dough into a 9-inch round tart pan, working it up the sides evenly. Prick the bottom with a fork about 15 times so steam can escape while baking. Chill in the fridge for 15 minutes before baking—this prevents shrinking and keeps edges from browning too fast.
Bake your crust at 375°F for 25 minutes until it's light golden brown all over. The edges should look just slightly darker than the bottom. Let it cool completely on the counter—this takes about 20 minutes and makes it way easier to add filling without melting.
While the crust cools, make your whipped cream filling by pouring heavy cream into a chilled bowl. Add powdered sugar and vanilla bean paste, then whip on high speed for 2 to 3 minutes until soft peaks form. I always chill my bowl beforehand because room temperature bowls make the whole process take forever and the cream sometimes splits.
Gently fold the whipped cream into a smooth custard base by whisking together cream, powdered sugar, and lemon juice until combined. Spread this filling evenly into your cooled tart shell, smoothing the top with a spatula. Don't press too hard or you'll deflate all those air bubbles you worked to create.
Arrange your berries on top of the filling in a beautiful pattern—alternating strawberry slices with blueberries and raspberries creates those gorgeous red, white, and blue colors. Start from the outside edge and work toward the center, placing berries close together so the filling barely peeks through underneath.
Drizzle honey lightly over the top of your patriotic fruit tart elegant using a small spoon or squeeze bottle. This adds shine and a touch of sweetness that pulls everything together. Refrigerate until serving time—the tart tastes best when it's cold and all the layers have time to meld.