Remove the sausage from the casings and tear into bite sized pieces. Heat 1T of olive oil in a 4-5 quart heavy pot or Dutch oven over medium heat. Add the sausage and cook, stirring occasionally, until browned, about 5 minutes. With a slotted spoon, transfer the sausage to a plate.

Add 1T of olive oil to the pot, increase your heat to medium high and add your onion. Cook, stirring frequently, until they begin to soften, about 2 minutes. Add your carrot & celery and cook until they begin to soften & brown, about another 2 minutes. Be sure to scrape up any brown bits from the bottom of the pan. Add your garlic, red pepper flakes, 1/2 t salt and 1/4 t pepper and cook, stirring, for about 1 minute more. Add your chicken broth and bring to a boil over high heat.

Once your broth comes to a boil, reduce the heat to medium, add your sausage with any accumulated juices and half of your beans. Mash the remaining beans with a fork and then add them to your soup. Stir to distribute. Add the kale and adjust the heat if needed to keep the soup at a gentle simmer. Cook until the kale is tender, about 15-20 minutes. Stir in the lemon juice, taste and season with more salt & pepper if needed. Serve.