This is a Tuscan recipe, so technique is kind of important. Start with a cold pot, put a couple rings of olive oil around the bottom, but don't turn on the fire just yet. I use my onion as my baseline for measurements. Finely dice the onion, then dice an equal quantity of celery and about half - 2/3rds carrot. Lightly salt the veg, stir it all up in the pot and then start your fire on medium low. You want to pouch the veg.
When the onions start to get translucent, add 3-4 cloves of minced garlic and a small container of mushrooms, let it set on top until the garlic becomes fragrant, then stir everything together. Add in 2-3 diced potatoes (hash brown sized dice), let them rest on top for a couple minutes, add a couple tsp of black pepper, 1 TBS Italian Seasoning, 2 TBS basil and then stir in.
Push the veg to the sides of the pan and add a pound of skinless/bulk Italian sausage and red pepper flake to taste (I also add a bit of smoked chipolte pepper). brown the sausage and break it up into small bites as you gradually combine with the veg. Once the sausage is completely brown, add two quarts of beef stock, stir it well and cover. Without adjusting your fire, let it come to a boil. Once you get to a boil, add a can of fire roasted tomatoes and a can of Cannellini beans (with the starchy juices), stir well, cover and let it come back to a boil. Taste, adjust your seasonings and then add kale or greens of your choice, simmer on low until the greens are tender.
I like to garnish each bowl with a three cheese mix (asiago, parm & romano) and fresh ribbons of sweet basil. This goes well with a nice artisan bread.