Heat olive oil in a large Dutch oven over medium heat until shimmering.
Add Italian sausage and cook for 5 minutes, breaking up with a spatula until browned and crackling.
1 Tbsp olive oil
Stir in diced onion; sauté for 3 minutes until translucent with golden edges.
1 pound bulk sweet Italian sausage
Add minced garlic, oregano, and red pepper flakes; cook 1 minute until fragrant.
1 small yellow onion, 2 cloves garlic, 1 tsp dried oregano
Pour in chicken broth and bring to a gentle boil, scraping up brown bits.
0.25 tsp red pepper flakes
Add broken lasagna noodles and reduce heat to a simmer; cook 8–10 minutes until al dente.
6 cups low-sodium chicken broth
Stir in heavy cream, ricotta, and Parmesan; heat 2 minutes until cheeses melt into a silky broth.
8 oz lasagna noodles, 1 cup heavy cream, 1 cup ricotta cheese
Add baby spinach and cook 1–2 minutes until wilted. Season with salt and pepper.
1 cup Parmesan cheese, 2 cups baby spinach
Ladle into bowls and garnish with chopped parsley before serving.
Kosher salt and black pepper