Brown the Sausage : Start by crumbling the Italian sausage into a large pot or Dutch oven. Cook it over medium-high heat until it’s nicely browned, breaking it up with a spoon as you go. Once done, transfer it to a plate lined with paper towels to drain excess fat.

Sauté the Aromatics : In the same pot, melt some butter and add chopped onion and celery. Sauté until they’re soft and fragrant, scraping up any brown bits from the bottom of the pot (those bits = flavor gold). Stir in minced garlic and flour, cooking for another minute or two to eliminate the raw flour taste.

Build the Broth : Slowly whisk in the chicken broth, ensuring no lumps remain. Add the half-and-half, Worcestershire sauce, crushed red pepper flakes, diced potatoes, and the cooked sausage back into the pot. Bring the mixture to a boil, then reduce the heat and let it simmer until the potatoes are fork-tender.

Season and Serve : Taste the soup and adjust the seasoning with salt and pepper. If you’re feeling fancy, stir in some kale during the last few minutes of cooking for added nutrition and color. Ladle into bowls, top with Parmesan cheese, and enjoy!