Leeks and potatoes gratin

We all need to empty the fridge and clean it once in a while. Many months have passed since the last time I cleaned my fridge and I finally reached the limit of acceptable procrastination. It is not that my fridge has become a jungle full of exotic slime eating animals, but there are bits of dried thyme here, some residual dirt in the vegetable compartment and some weird dried spill marks that appeared without anyone ever knowing what caused them. We also tend to accumulate a few long lasting items such as pickles, sauces or leeks and potatoes which have past their prime.

A few days ago, we decided that we would not do any unnecessary groceries before our fridge was empty and clean. It would allow us to restock it with fresher ingredients and to enjoy nicer looking shelves. This is why we made this leeks and potatoes gratin using half an onion that was sitting on the top shelf, cheese leftover from the pizza I made recently, the leeks and potatoes as well as all the ingredients needed to make a nice béchamel.
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First step: I caramelized the little onions I had to add flavour to what could have been a very bland dish.

Second step: I made a thick béchamel and added a pinch of nutmeg to it.

Third step: I blanched the potatoes and the leeks.

Fourth step: I mixed everything together and topped the resulting mixture with cheese.

Fifth step: I baked it in the oven for a few minutes.

The result was surprisingly good. Cooking magazine would talk about its rusticity but I'll just say that it was really nice to have this dish sitting on the table. The days are getting colder and colder and comforting and rich flavours are what we crave for in such circumstances.