In a 9" round pan, add 3/4 cup sugar and caramelize on cooktop (works best with gas range -- do not add water; do not stir -- just shake pan around until sugar is rich amber color -- set aside to cool
Combine egg yolks, sweetened condensed milk, and vanilla. Whisk well. Fill one of the milk cans with cold water. Whisk that in as well.
Pour mixture through a strainer into the pan with the hardened caramelized sugar
Place in a water bath and bake at 350 for at least an hour. Cook until the center is just slightly jiggly still. Do not cook until the center is completely firm as it is overdone at that point. The flan will continue to cook once you take it out of the oven.
Once removed from oven, cool on counter for at least an hour.
To serve, slide butter knife around edges. Then, place a plate on top of the pan and flip the whole thing upside down. The flan should fall out onto the plate. Scrape excess caramel out of pan onto the top of the flan. Slice and serve.