In a large soup pot, sauté garlic and onions in olive oil over medium-high heat until the onions are translucent.
Add oregano, potato, tomatoes and vegetable stock, bring to a boil.
Reduce heat to low and simmer for 10 minutes until potato softens.
Using an electric hand blender, blend hot soup over the stove. Alternatively, you can allow mixture to cool and transfer to a standing blender before returning to the same pot.
Once the mixture is blended, return to medium heat, add lentils and frozen spinach, bring to a boil, stirring constantly.
Reduce heat to low and simmer for another 10 minutes until spinach is entirely incorporated.
Add salt and pepper, to taste.
Turn off heat, divide into eight small portions or four large. Sprinkle with parmesan, vegan parmesan or nutritional yeast [optional].