Lemon blueberry pavlova

Cut up the butter and set aside. Separate the eggs; cover the whites and leave them at room temperature.

Whisk the yolks with the lemon zest, a small pinch of salt, a slightly larger pinch of sugar and the lemon juice.

Set the bowl over an inch or two of barely simmering water, not touching, and stir constantly with a spatula (not a whisk, to avoid air) about 10 minutes until very hot and thick enough to coat a spoon.

Stir in the butter three or four pieces at a time, each melted before the next; take off the heat and pour into a bowl (strain if wanted).

Press plastic onto the surface and chill the soft lemon curd completely.

Lightly oil a silicone mat on a sheet pan. Stir the cornstarch into the sugar.

Add the cream of tartar, a little lemon juice and vanilla to the room-temperature whites; whisk to very soft peaks.

Whisk in the sugar mixture a couple of tablespoons at a time, about a minute each, then whisk to relatively stiff peaks that hold sharp lines, not so far it turns dry and grainy.

Spoon big dollops in a ring 8 or 9 inches across, fill the centre at least an inch thick, then add a second layer of dollops round the edge with swirls on top.

Bake in the centre of a 250F oven for exactly one hour; turn off the oven, crack the door and let it cool completely inside.

For the sauce, simmer fresh blueberries with a couple spoons of sugar and a splash of cold water on medium about 10 minutes, stirring, until the berries collapse and it thickens; press through a fine mesh strainer and chill.

Loosen the meringue with spatulas and transfer to a plate; crack the centre a little with a spoon to make a well.

Fill the centre with the lemon curd, pile on fresh blueberries, drizzle with blueberry sauce and finish with a sprig of mint.