Preheat oven to 400°F (200°C). Line a baking sheet with parchment paper. Spoon 2-tablespoon mounds of freshly grated Parmigiano Reggiano about 2 inches apart, flattening slightly. Bake for 5 to 6 minutes until golden and bubbling. Let cool 5 minutes until crispy.

In a large 5 to 6-quart enameled cast-iron Dutch oven, heat olive oil and butter over medium heat. Add diced onion and cook for 5 to 6 minutes until soft and translucent.

Add minced garlic and tomato paste. Cook for 2 minutes, stirring constantly until the paste darkens to a deep brick red and releases a rich, sweet fragrance.

Pour in the crushed San Marzano tomatoes, broth, dried oregano, red pepper flakes, salt, and black pepper. Bring to a boil, then reduce heat to low and simmer gently for 10 minutes to marry the flavors.

If you prefer a completely silky soup, use an immersion blender to puree the tomato broth until smooth (or leave it slightly rustic with tender onion bits). Stir in the heavy cream and 1/2 cup grated Parmesan cheese.

Bring the soup to a gentle simmer. Add the fresh refrigerated cheese tortellini and cook for 3 to 4 minutes until they float to the top and are tender al dente.

Stir in the fresh baby spinach and fresh basil ribbons. Remove from heat immediately—the residual heat will wilt the spinach into vibrant green ribbons within 60 seconds.

Ladle into warm bowls. Garnish with freshly grated Parmesan, cracked black pepper, fresh basil leaves, and perch a golden Parmesan crisp on the rim. Serve immediately with warm garlic focaccia!