Using a food processor - place the flour and butter in the food processor and pulse until it resembles crumbs.By hand - rub the butter into the flour until is resembles crumbs.
Add the sugar and mix.
Add a small amount of water (just enough to bind the pastry dough) and pulse (or mix by hand) until the ingredients form a ball of dough.
Roll out on a floured board to a thickness of about 3 mm and line a 20 cm (8") diameter tart dish.
Prepare the filling
Mix the butter and sugar together.
Add the egg, ground almonds and almond essence and beat either by hand or with an electric mixer.
Assemble the tart
Spread the almond frangipane mixture evenly over the base of the tart shell.
Peel, core and slice the pears and arrange over the top of the almond mixture pressing slightly into place.
Bake
Cook at 180oC, 350oF, gas mark 4 for around 30 to 40 minutes or until the filling is firm and slightly golden.
Notes
To serveLeave to cool and serve cold either on its own or with double cream, whipped cream or ice cream.To storeStore in an airtight container until the following day.