Blueberry Jam Mont Blanc Pastry Recipe

Make the dough

Whisk together flour, icing sugar and fine salt in a bowl. Add cold cubed butter and rub between your fingers or use a pastry cutter until the mixture resembles coarse crumbs with some pea-sized bits of butter remaining.

Bind dough

Whisk the egg yolk, vanilla and cold water in a small bowl. Add to the flour-butter mixture and quickly fold with a spatula or your hands until the dough comes together. Do not overwork. If the dough is too dry, add up to 1 teaspoon cold water.

Chill and roll

Form the dough into a disk, wrap in plastic, and chill in the refrigerator for 30–45 minutes. Preheat oven to 350°F (180°C). On a lightly floured surface, roll the dough to about 1/8-inch thick. Cut into rounds to fit 4–6 tartlet pans or one 9-inch tart pan with removable bottom.

Blind bake

Line tart pans with dough, trim edges, and dock the bottoms with a fork. Chill shells for 10 minutes in the fridge. Line with parchment and fill with pie weights or dried beans. Bake for 12–15 minutes, remove weights and parchment, then bake 5–8 minutes more until lightly golden. Cool completely on a rack.

Cook blueberries

Combine blueberries, granulated sugar, water, and lemon juice in a small saucepan over medium heat. Stir to combine and bring to a gentle simmer. Mash berries with a potato masher or the back of a spoon to release juices.

Reduce to jam

Simmer, stirring occasionally, until mixture thickens and coats the back of a spoon, about 12–18 minutes. If using pectin, sprinkle it in during the first 2–3 minutes of simmering and stir to dissolve. Taste and adjust sweetness or lemon as desired. Remove from heat and cool. Strain through a fine mesh sieve if you prefer a smoother jam; otherwise leave with small berry pieces.

Prepare chestnut purée

If your chestnut purée is very thick, loosen it by stirring in the room-temperature butter and vanilla until smooth. If you want a sweeter cream, sift in powdered sugar and mix. Chill briefly if the mixture becomes too soft.

Whip cream and finish

Whip the heavy cream to soft peaks. Fold about one-third of the whipped cream into the chestnut purée to lighten, then gently fold in the remaining whipped cream until homogeneous and smooth. Transfer mixture to a piping bag fitted with a 1/2-inch round or Mont Blanc tip (or use a small star tip if preferred). Keep chilled until assembly.

Preheat and prepare

If making meringue bases, preheat oven to 225°F (105°C) and line a baking sheet with parchment.

Make meringue

In a clean, dry bowl, whisk egg whites with a pinch of salt and cream of tartar until foamy. Gradually add granulated sugar while beating to medium-high speed until glossy stiff peaks form and sugar is dissolved (rub a little between fingers to check for grittiness).

Pipe and bake

Pipe small disks (about 2.5–3 inches) or nests onto the parchment to fit inside your tart shells. Bake at 225°F (105°C) for 60–75 minutes until dry and crisp. Turn oven off and let meringues cool completely inside oven to avoid cracking.

Layer jam

If using tart shells: spoon or pipe about 1–1.5 tablespoons of blueberry jam into each cooled pastry shell, spreading into an even layer. If using a single tart, spread jam evenly across the cooled tart shell (about 1 cup).

Add meringue (if using)

If using meringue bases, place one meringue disk in the center of each jam-filled shell. The meringue adds crunch and traditional Mont Blanc texture contrast.

Pipe chestnut cream

Using the prepared piping bag, pipe the chestnut cream over the jam (and meringue, if used) in continuous spaghetti-like strands or concentric rings to create the classic Mont Blanc mound, covering the center and building a small dome. Aim for about 2–3 tablespoons chestnut cream per tartlet (more for a large tart).

Finish and garnish

Dust lightly with confectioners' sugar. Place a fresh blueberry on top of each Mont Blanc and a small mint leaf if using. Chill assembled pastries 15–30 minutes to set before serving. Serve within 24 hours for best texture.