Place the plant-based beef in a mixing bowl. Add the panko, chopped parsley, garlic, oregano, fennel seeds if using, black pepper, and salt. Mix with clean hands until evenly combined.

Form the mixture into compact meatballs, each roughly 1 tablespoon in size and set on a tray.

Warm the olive oil in a wide skillet over medium-high heat. After 90 seconds, when the oil is hot, add the meatballs in a single layer without crowding. Brown over medium heat for 7-8 minutes, turning every 2 minutes so all sides are lightly browned. Transfer the cooked meatballs to a plate.

In a large heavy-bottomed pot warm the olive oil over medium heat. After 90 seconds, when the oil is hot add the onion, carrots, and celery. Sauté over medium heat for 8–10 minutes, stirring regularly, until the fresh vegetables soften.

Add the garlic, oregano, thyme, and crushed red pepper flakes. Continue to sauté for 90 seconds, stirring continuously.

Pour in the vegetable stock and add the salt. Increase to medium-high heat and bring to a steady boil.

Stir in the acini de pepe and reduce to medium heat for 6–8 minutes, or until the pasta is al dente, stirring every 2 minutes to prevent sticking.

Add the browned meatballs, chopped parsley and spinach, and simmer over low heat for 5 minutes so the meatballs heat through and the greens wilt. Taste and adjust salt as needed.

Ladle into bowls and garish with grated vegan parmesan and minced parsley if using.