With the rack in the lowest position, preheat the oven to 190 °C (375 °F).
In a large skillet, brown the onion in the oil. Add the spinach and garlic and sauté until the spinach has wilted. Season with salt and pepper. Drain in a sieve. Set aside.
In a bowl, combine the eggs, cheese, and cream. Add the spinach mixture. Season with salt and pepper.
On a work surface, overlay six sheets of phyllo, rotating each 1/6 of a turn and brushing each sheet with butter.
With the dough, line a 23-cm (9-inch) pie plate. Pour the spinach mixture into the pastry and fold and crumple up the dough onto the filling. Brush with butter. Bake for about 45 minutes or until the pastry is golden brown.
You can serve this pie with tomato or marinara sauce.
Recipes with the "Healthy Pick" stamp have been evaluated by a registered dietitian member of the Ordre professionnel des diététistes du Québec.