Set a large skillet over medium heat. Add in the olive oil. When hot, cook the onion in the oil for 2 to 3 minutes, until it starts to soften. Add in the zucchini, eggplant, corn, tomatoes, garlic, salt and red pepper flakes. Cook for 7 to 9 minutes, until the veggies are tender. Remove from the heat, taste and season with additional salt and red pepper flakes if needed.
Spread ½ cup of the sauce in the bottom of your slow cooker. Top with a layer of three lasagna noodles, breaking them as needed to fit. Using a slotted spoon, top with ⅓ of the vegetable mixture, then ½ cup of the sauce and ⅓ cup of the mozzarella cheese. Repeat this process two more times -- noodles, vegetables, sauce, cheese. End with a final layer of noodles and the remaining ½ cup of the sauce. Sprinkle the top with the remaining ⅓ cup mozzarella, the parmesan and panko.
Cover and cook on low for about 3 ½ to 4 hours, until the noodles are cooked through. Turn off the slow cooker and let sit uncovered for 20 to 30 minutes before serving. This will let the lasagna set so you can cut it easily and it will hold its shape. Sprinkle the top with fresh basil before serving.
Notes
Make sure you use regular uncooked lasagna noodles. Do not use the no-boil kind. For the canned tomato sauce, I used around 1 (15 ounce) can and 1 (8 ounce) can to get this amount.It is possible to find vegetarian parmesan cheese in the US (such as the Whole Foods 365 brand or Organic Valley). Outside the US, look for vegetarian hard cheese to use instead.
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