Separate an egg, and keep the yolk in a bowl big enough to hold about 1.5 cups. You do not need the white for this recipe. In a mortar and pestle, mash into a paste six very small cloves of garlic with a large handful of salt. Rinse two canned anchovies, fillet them and pick out the bones, and rinse again to wash off all the weird canning salt; add the anchovies to the mortar and pestle and mash into the garlic paste. To the egg yolk add 1/8 tsp water and the garlic-and-anchovy, and whisk it all together. Measure 1 cup olive oil into something with a pour spout, and dribble a little oil into the egg yolk. Whisk, and dribble a little more in, whisking all the while. The egg yolk mixture will lighten in color and thicken; then you can start pouring in larger splashes of oil, until the entire cup is incorporated. Cover the aioli with saran wrap and refrigerate a few hours until ready to serve.
Wash, dry, and rip one or two heads Romaine lettuce. Also wash and cut into eighths 4 early girl tomatoes and add to the salad. Add the aioli, and some grated and some shredded Parmesan cheese. Enjoy with a large loaf of sourdough bread.