Like a good gumbo, the key to this recipe is cooking the roux for longer than one would expect to do. Unlike gumbo where the roux is cooked for an hour or so, this soup needs a ten minute roux cook off in two stages.
First stage is after the onions have been cooked until tender, lower the heat and mix in the flour. It needs to cook, with constant stirring for five minutes, so the heat has to be low enough so the roux does not dry out. Long roux cook time is your friend in this recipe.
Second stage is adding the water in several increments, about two tablespoons at a time, and fully incorporating the water before adding more. This stage should take about five minutes.
This method has resulted in a soup that after the meal, the soup tureen being wiped clean by one or more people with bread slices or dinner rolls to get the very last bit. As with all recipes, your mileage may vary.
To get the tomatoes peeled, cored and seeded, the tomato press has served itself well as one of the few specialized items in the kitchen, but the old school method of parboiling and manually doing the task works quite fine.
In the list of ingredients, the bay leaf is noted as being optional as over the years sometimes a bay leaf was not available yet the soup was well received.
To make it vegan and gluten free, a variety of vegetable oils and gluten free flour mixes have been used successfully. However, so far, the most luxurious mouth feel has been with the butter/regular all purpose flour combination. If someone comes up with a top notch vegan/GF version that provides a wonderful "creamy" mouth feel, please share as I always seek to provide people with special dietary requirements an equal version in all aspects. Thank you in advance.
Additionally, this recipe scales up nicely, at least up to 20 quarts. —Misha
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