This is my official favorite quiche base. I've kitbashed it three different ways now, in addition to the original recipe, and it's been fantastic every time.
The latest version: instead of spinach, I sauteed with bacon 1 each carrot, tomato, smallish zucchini and yellow squash, and half a red onion until soft; subbed swiss and parmesan cheeses for cheddar, and baked the quiche in a deep dish pan (very important). I've also used broccoli in the veggie mix and ham instead of bacon.
It's versatile and not too heavy with only 2 eggs. Works fine with 1% milk, doesn't need cream like some other quiche recipes.