Preheat oven to 200° C.
Add flour, butter, chia seeds and a pinch of salt to food processor and blend until crumbly.
Add egg and blitz until the mixture comes together in clumps.
Turn mixture onto clean board and knead into round ball. Cover with cling wrap and set aside in refrigerator for 30 minutes.
Place pumpkin, shallots and sage on a baking tray and drizzle with Extra Virgin Olive Oil and bake in oven for 20 minutes, or until pumpkin becomes soft and golden brown.
Remove dough from fridge and flatten with rolling pin. Place the dough over a loose-bottomed tart tin and trim the edges.
Blind bake pastry for 15 minutes.
Add feta to pumpkin and shallot mixture and spoon into tart base.
Bake in oven for 20 minutes, or until golden and cooked through.