Preheat the oven to 200 °C and grease the spring form pan. Brush the slices of puff pastry with oil and place them in the pan. Allow them to protrude slightly over the edge. Bake the base in the oven for about 10 minutes.
Heat some olive oil in a frying pan, add the spinach bit by bit and cook while stirring. Spoon the spinach in a strainer and squeeze as much moisture as possible from it with a spoon.
Remove the spring form pan with the base from the oven and fill it with spinach. Beat the eggs with the ricotta, mix the raisins and season to taste with salt and pepper. Pour the mixture over the spinach. Bake the pie for 35-40 minutes in the oven until golden brown and cooked through. Allow the pie to cool and garnish with sliced tomato, some fresh mint and crumbled feta.