**Get the broth ready.** Dissolve a stock cube in 3 cups (720ml) of just-boiled water and set aside. Using a carton? Measure out 3 cups and keep it next to the stove.

**Sauté the vegetables.** Melt the butter in the olive oil in a large pot over medium heat. Add the onion and carrots. Cook for 5–6 minutes, stirring occasionally, until the onion is soft and see-through (not browned). Add the garlic and stir for 30 seconds.

**Bloom the paste and cook the flour.** Add the tomato paste and stir constantly for 2 minutes until it darkens slightly and smells sweet rather than sharp. Add the flour and stir for 1 more minute. The mixture will look thick and paste-like.

**Add the liquid and simmer.** Pour in the diced tomatoes, tomato sauce, broth, Italian seasoning, and red pepper flakes (if using). Stir well to scrape up any bits from the bottom. Bring to a gentle simmer and cook for 8–10 minutes.

**Cook the tortellini.** Add the tortellini and cook for 3–5 minutes (or per package directions) until just tender — test one by cutting it in half; the dough should be soft all the way through.

**Finish off the heat.** Take the pot completely off the burner. Stir in the cream, then the Parmesan, then the spinach. The spinach will wilt in about 30 seconds. Season generously with salt and black pepper.

**Serve** hot, topped with extra Parmesan and fresh basil. Crusty bread on the side for dunking.