- In a saucepan, combine all the ingredients and bring to a boil. Simmer for 10 to 30 minutes, depending on the ripeness of the pears, or until tender.
- In a food processor, combine the flour, sugar, and salt. Add the butter and pulse for a few seconds at a time, until the butter is the size of peas. Add the egg, water, and vanilla. Pulse again until the dough just begins to form. Add water, if needed. Remove the dough from the food processor and form a rectangle with your hands.
- On a floured work surface, roll out the dough into a 3-mm (1/8-inch) thick rectangle. Line a 33 x 10-cm (13.5 x 4-inch) rectangular pie plate with a removable bottom. With a fork, prick the bottom of the crust. Refrigerate for 30 minutes.
- With the rack in the lowest position, preheat the oven to 200 °C (400 °F).
- Bake the crust in the oven for 15 minutes. Reduce the oven’s temperature to 190 °C (375 °F).
- In a food processor, combine the almond paste, butter, and flour until smooth. Add the egg and process until everything is smooth. Set aside.
- In a small bowl, combine the almonds, sugar, and lemon juice. Set aside.
- Spread the almond paste filling into the hot crust. Cover with five pear halves, cut side down, alternating the direction of the pears. Sprinkle the slivered almonds mixture over the pie. Bake for about 35 minutes or until the pie is golden brown.
- Serve the pie warm or cold.
In you can’t find a rectangular pie plate with a removable bottom, use a 23-cm (9-inch) round pie plate.