Finally, Mush

I got up this morning and thought, I'm going to make some lentil soup! In the past my lentil soup has sucked, and only recently did I discover why: I added salt to the water when I cooked the lentils, thereby rendering the wee legumes tough and chewy, when they should be veritable mush. Once a friend clued me on this grievous error on my part, I again dared dream that I could make a lentil soup as delicious as the canned Giant Eagle store brand (best canned lentil soup on Earth).
The recipe I have for lentil soup calls for olive oil, but in a fit of brilliance, I opted for butter. A whole stick of butter!
Roughly, here's what I did:

Emptied an entire 16oz bag of lentils into a large pan, covered with 5C of water, simmered for two hours (I wasn't taking any chances that I wouldn't get mush)
Added 4C of beef stock
1 can of stewed tomatoes
2 stalks of celery chopped
1 medium onion diced
2 carrots finely chopped
whole stick of butter
six leaves of baby spinach chopped
salt and pepper to taste

I cooked the soup for another hour or two on very low heat, stirring it when I got up to get more coffee. Finally, the soup was served over thin spaghetti.
I don't know why, but lately my favorite comfort food is lentil soup over pasta. Maybe it's all that butter - which I even add to the canned soups, an old trick my German Grandmother used to employ. She lived to be 90, so I'm guessing that this can't be too bad, right? One more butter fact: When I was a kid my mother used to add a pat of butter to our mugs of coco. For years I was scandalized that my friends' mothers didn't do the same. I was such a sheltered fool. Little has changed in the ensuing decades.