About six years ago, I did not know what a leek looked like. I knew that they tasted good in soup, but I had never seen a full fledged fresh leek. They basically look like giant green onions.
You've got to rinse them, otherwise there's nothing but nasty sand in your food.
Then with a wide glass, can, or other round object, trace and cut out as many circles as you can.
Put each dough circle into your muffin tin, and fill halfway with cooked leeks.
Then fill up each cup with a roughly half and half combination of eggs and dairy. I tend to combine heavy cream, half and half, and fat free milk to get a sort of full-fat milk equivalent, but if you want to just use low-fat milk, or just cream, that's fine too. It depends how creamy you want your tartelettes to be.
Finally bake at 350F for about 45 minutes, and you've got the perfect appetizer, or light dinner with a couple on each plate and a side of salad.
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Apparently there's a booth at our farmer's market that should be getting leeks again soon! Strange season, but I'll take them. Maybe I'll make soup.