Pre-heat oven to 375°F (190°C).
In a large ovenproof skillet (10 to 12-inches/ 25 to 30 cm and 2-inches/5 cm deep), heat oil over medium heat. Sauté onion, oregano and basil for 5 minutes or until onions are transparent. Add garlic and sauté 1 minute. Add mushrooms and zucchini; sauté for 5 minutes or until vegetables are slightly soft. Add diced tomatoes and pasta and simmer for 10 minutes.
Remove skillet from stove and spoon out all but one-third of sauce. Top with a layer of lasagna noodles, breaking as needed to fit in single layer. Add another layer of sauce and noodles. Top noodles with spinach and crumble half of the feta over the spinach. Top with another layer of noodles. Spoon remaining sauce and crumble remaining feta on top.
Place skillet in the oven and bake for 30 to 45 minutes or until bubbly.