You'll need one pound of brown lentils, several onions, 1 28 ounce can of tomatoes, salt, butter, and about 2 hours. 

First, chop the onions.  When Gram wrote the recipe down for me, she said 4-5 medium onions.  I find the onions I usually have on hand from my CSA Farm Share are much larger, so I'll only need 2, maybe 3.  You want approximately 2 cups, chopped.

Next, melt the butter on medium low heat.  You can use from 2-4 tablespoons, depending on how rich you want the soup.  I know that southern Italian cooking usually uses oil, not butter...but Gram refused to use oil.  (She said it was because she had been forced to drink a spoonful of castor oil every day as a child (back in the early 1900s), but whatever the reason, that's what we did in my family - always butter, never oil.  She lived until she was 95, so the butter didn't hurt.)

Saute the onions in the butter until golden and they just begin to brown around the edges. Don't rush this, as this is where the soup's flavor develops.

When the onions look good, add the tomatoes.  You want the best you can afford. I typically use either tomatoes from the garden that I've frozen, or Bianco di Napoli, but as long as they taste good, whatever brand you like will work. Whole tomatoes are fine, as they will cook down.  Chopped are okay as well, but don't use commercial "diced" tomatoes - they are treated with something to keep their shape and they won't dissolve into the soup.

Simmer the onions and tomatoes for 25 minutes.

Rinse the lentils, and add to the onion mixture. Stir for a minute or so, add salt to taste (Gram would usually add a tablespoon, which is more than modern tastes can handle, lol).

Add 6 cups water.  If the soup is thicker than you like, you can add more water as they simmer.

Simmer for about 45 minutes, until the lentils are tender.  If you feel like splurging, slice a package of hot dogs into disks and add 10 minutes before serving.

We would always have these with fresh bagels and butter on the side, but when I don't have fresh baked NY Bagels on hand, I have found that crusty bread works just fine.

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