Preheat oven to 350 degrees Fahrenheit (180 degrees Celsius).

Slice the onion very thinly and place in a heatproof bowl. Pour boiling water on top and allow to sit for 30 seconds. Drain well.

Sprinkle half the cheese on the pie crust, then add the onion slices. Slice the lox and add it on top of the onion, then sprinkle with capers.

Dot the top with cream cheese (chopped, if it’s block cream cheese, or small dollops if it’s whipped). Sprinkle with remaining mozzarella cheese.

Combine the eggs and milk and pour over the quiche. Sprinkle with everything Spice and bake for 45 minutes or until completely set.