Double Onion, Cheese & Tomato tart

This totally delicious tart was a variation on the Stephanie Alexander Cheese & Onion tart recipe I've made before, from her encyclopaedic Cooks Companion ; a must for any kitchen. I was making some pastry (the perfect pate brisee with dried thyme I found on Clothilde's site) for little tarts to take to a function, and had some leftover. Almost enough to completely line a proper tart pan with a removable bottom, although I didn't quite make it up all the sides and it was a little thin for the creamy filling I made, but I felt very proud of making a tart with a homemade crust for dinner, and not using frozen pastry sheets, as we usually do...

I didn't have enough onions for the recipe so added half a bunch of spring onions (scallions/shallots, depending on what part of the world, or Australia you're in). There still wasn't quite enough bulk to the amount of eggs and liquid involved, but I really enjoyed it that way; it made the filling taste like creamy scrambled eggs; yum! I used a combination of some Havarti cheese from Greece, and a creamy blue cheese I keep in the freezer, because that way it grates really well and you tend to use it in moderation (a good thing when it's expensive and unhealthy, and you have a tradition of eating far too much of it!).
I had some light sour cream in the fridge and used that instead of cream, and then chose to slice a perfect ripe tomato to layer over the top. I think this really made the dish perfect; the creaminess of the filling was perfectly offset by the sweet/salty tomato on top. Early Autumn is the best time for tomatoes in Melbourne, and these homegrown versions did not disappoint.
Served with some rocket I found in the vegetable crisper made this a sophisticated dish for dinner, and there was enough for lunch the next day too!