Rinse spinach leaves individually and place them in a saucepan. Cover and
cook over medium heat, with just the water clinging to the leaves, until the
spinach is steaming and wilted (about 2 minutes).
In another saucepan, heat vegetable oil and sauté onion, garlic, oregano
and basil until onion is soft. Stir in thyme and tomatoes. Cover and cook 20
to 30 minutes.
Cook lasagna noodles for 10 minutes in a large kettle of boiling water to
which 1 tablespoon oil has been added.
Oil a 13 x 9-inch baking pan and pour in enough of the tomato sauce to cover
the bottom. Add layers in the following order: noodles, spinach, ricotta, mozzarella,
Parmesan and tomato sauce. Repeat until all ingredients are incorporated.
Bake at 350 degrees F for 35 to 45 minutes, or until the cheeses are melted
and the sauce bubbles.
Remove from the oven and let stand 15 minutes before cutting in squares