In a large pot over medium-high heat, add the olive oil and wait until it warms up. Then add the diced onions. Sauté the onion until they soften up—about 2 mins.
Next, stir in the minced garlic and sliced mushrooms. Continue sautéing for another 2 minutes until they’re fragrant and start sticking to the pot.
If you're using it, add in the ground beef, along with the salt, black pepper, and oregano. Sauté over high heat until the meat is fully cooked and any liquid has evaporated.
Now it’s time to add the crushed tomatoes and stock. Stir in the minced basil and a little extra oregano. Bring the soup to a boil.
After the initial boil, add the lasagna noodles. Stir to combine and let them cook for about fifteen minutes until tender.
Once the noodles are cooked, add in the ricotta cheese. Gently mix it in until it completely dissolves into the tomato sauce.
Turn off the heat and fold in the remaining fresh basil. The heat from the soup will gently wilt the basil, releasing its fresh aroma and flavor.
Lastly, serve the soup in bowls, sprinkling some grated cheese on top if you like. Taste and adjust the seasoning with more salt and pepper.
