In a high frying pan, sauté the onions in a little oil until translucent. Add the bacon and fry until lightly crispy. Add the garlic and fry briefly. Add the frozen creamed spinach. Reduce the heat and continue to cook until the spinach is thawed.
Whisk the eggs with the milk and season with salt and pepper.
Place the cake batter together with the baking paper in a baking tray. Prick the pastry base several times with a fork. Put the glaze in the high frying pan with the spinach and mix in. Spread the contents of the pan on the dough base. Bake in a preheated oven at 220 ° C for about 35 minutes.
Remove, cool a little on a wire rack, remove from the tray and serve.