This is not a complicated tart to make, because you can use ready-made pastry and whip up the filling in a food processor, but it looks so impressive!
If nectarines are not available, use pears, but be sure to choose ones that are not wooden.
400g (14 ounces) ready-made sweet shortcrust pastry
100g (3½ ounces) unsalted butter, softened
90g (3 ounces) caster (superfine granulated) sugar
1 Tbsp standard flour
2 large (size 7) free-range eggs, at room temperature
120g (4 ounces) ground almonds
5-6 just ripe nectarines
Small jar inexpensive apricot jam
Splash lemon juice
Vanilla ice cream, plain yoghurt or runny cream, for serving
1 Roll out pastry on a lightly floured surface and line into a 23cm (9 inches) loose-bottomed flan ring set on a baking sheet lined with baking (parchment) paper. Prick all over with a fork, then chill until pastry is firm.
2 To make the frangipane put butter and sugar in the bowl of a food processor and whip until smooth and paler in colour (1-2 minutes), scraping down the sides of the bowl 2-3 times. Add the flour. Beat eggs lightly together with a fork. With the machine running, gradually whip in the eggs, then whip in ground almonds. Spread frangipane over bottom of pastry. If you don’t have a food processor, use a hand-held electric beater to beat butter and sugar together, add flour and gradually beat in the eggs then the almonds.
3 Preheat oven to 190°C (375°F). Put a baking sheet to heat on a shelf set in the bottom third of the oven.
4 Cut nectarines into thin wedges. Arrange on top of the frangipane. Slide tart with the paper onto the heated baking sheet in oven and bake for 35-40 minutes, or until pastry is cooked on the base and filling is nicely golden on top.
5 To make the apricot glaze, sieve jam into a small pan, bring to a gentle bubble and add lemon juice. If glaze is thick and sticky, thin it with a little hot water. If it is too thin, bubble it away to reduce. Using glaze while piping hot, brush over top of tart. Cool tart before slicing into portions. Serve with ice cream, yoghurt or runny cream.