Bean soup - 20 minute meals

I like to eat home made and tasty food, but sometimes time is an issue. I suppose it's not just me...
I noticed in Finland that people tend to buy ready made food on a regular bases on the way home (I get creeps just thinking of those tasteless "laatikko"s.. grrr...) (and here they go to fast food or cheap restaurants) because they think of the cooking as some kind of tiring gourmet exercise, while an everyday cooked meal is not, or at least shouldn't be.
We have invented couple of 20 minutes meals (or just brought them from home) that are tasty, healthy and are ready in ~20 minutes, about the same time it takes to dress up a family and drive to the nearby fast food. The ingredients are all non-perishable, canned, with minimal effort is easy to guarantee that you have some hiding in your storage.
If you can afford spending 20 minutes in the kitchen after you arrive home (and the kids won't roll on the floor in a terrible temper tantrum caused by hunger), this is a meal one can consider.
They have now organic canned beans on discount at Sprouts, so it looked like a perfect opportunity to empty and refill our provision, besides, yesterday only the dog and the youngest wanted to eat baby ribs, everybody else was fed up of meat.
A big plus eating these easy, home made meals is that your kid won't get used to the mass taste of fast food and will be a more balanced eater.
Sorry for the big portion, I never made it smaller, even with this quantity is a battle who gets to eat a second round. I took a pic with less zest to show the "content", you will however have a much more juice soup, just like most of the Hungarian soups are..

Ingredients (makes 4 litres)
3 tbsp oil
3 flat tbsp flour
1 small yellow onion
200 g frozen green beans, preferably cut into ~ 1 in pieces (if you don't have any in the freezer don't panic, is gonna be good enough without)
1 can organic pinto beans
1 can organic kidney beans
1 can organic white beans
1 can black beans
spices: salt, black pepper, paprika powder, vinegar
optional (but good): 1 small tomato cut into 4, 1 tsp minced red paprika pure or 1/2 small  fresh paprika (any type)
2-3 tbsp fresh Italian parsley (chopped if you like, leave it un-chopped if you don't like the parsley floating in your soup)
PS. Feel free to replace any of the beans with another one, I just like a colorful plate and tend to put more types of beans because of the look rather than the taste.

Serving
sour cream
fresh bread (optional, if you wanna skip bread)
spring onion, or thinly cut and salted onion slices, or paprika slices (optional)

In a pot put the oil to the heat, when the oil is hot add the flour, stirring continuously "fry" the flour just for 1 minute or two until gets golden, remove from the heat, add the tbsp paprika powder, stir it in the oily flour base (we call it rántás), and pour in water, about 2.5 litres. Put it back to the stove, and the onion and the green beans, the fresh or minced paprika, the tomato and cook it for ~15 minutes. The frozen green beans should be cooked during that time. You can remove the cooked tomato and paprika if the family doesn't like them.
Meanwhile empty the bean cans in a strainer and wash them thoroughly, I never liked the sauce of the cans as it is so thick, and I have no clue what they used to thicken it.
Add the beans to the pot, season with salt until you like the taste, black pepper (~1/4 - 1/2 tsp) and add 2 tbsp of parsley, bring to boil, now add ~1 l milk (1/4 gallon), and boil for an additional 5 minutes at lower heat. Be careful not to have your milk running all over you stove, you might want to stir occasionally.
Let it cool down for a while, then add some vinegar. How much? it depends on you. From 0.3 dl to 0.5 dl to none or more, it is all a personal taste. It is wiser not to add too much if you haven't tried yet, you can add more when served individually (but watch the quantity, being so small is becoming tricky).
Serve as is, with a tbsp of sour cream/plate, sprinkled with more fresh parsley, with spring onions, onion slices, or paprika slices. In my opinion the sour cream is a must :D, and the onion is also on the edge to deserve the "must" category.
I think it took me longer to write this blog then to make today's lunch.. :)
Bon apetite.