Heat olive oil in a Dutch oven over medium heat. Add onion and celery, cooking 5 minutes until translucent. Stir in garlic and Italian seasoning for 60 seconds.

Add tomato paste and cook 3 minutes until rust-colored. Pour in diced tomatoes, chicken broth, water, cannellini beans, and crushed red pepper. Simmer gently 8 minutes without boiling.

Cook pasta separately in salted water 1 minute less than package instructions. Drain and shock in ice water. Add pasta to soup just before serving.

Stir in spinach and lemon juice off-heat. Adjust salt if needed. Serve soup topped with pasta, Pecorino, red pepper flakes, and celery leaves.