If using fresh tomatoes, deseed the tomatoes (if you wish remove the skins). Bring the tomatoes to a boil and add the minced garlic, chopped basil, crushed fennel seeds, ground oregano, olive oil, sugar, and salt to taste. Simmer until thick and reduced (may take up to an hour). It’s important to use a thick lasagna sauce in this recipe because the lasagna can otherwise be on the soupy side without the pasta to soak up the extra liquid as it bakes.