Prep: Preheat the oven to 420F, with one rack in the middle of your oven and another in the upper third. Set a 9x13” casserole dish (preferably with a lid) and a large baking sheet to the side.
Dump: Rinse the lentils and quinoa well, then add them to the casserole dish along with the tomatoes, bell pepper, and sweet potato. Sprinkle all of the spices and seasonings on top of the casserole, then pour in the vegetable broth. Mix well and cover the casserole with a lid or tightly fitting aluminum foil.
Bake the Casserole: Place the baking dish in the middle rack of the oven and bake for 60 minutes, or until the lentils are tender and the quinoa is fully cooked.
Crispy Kale: In the meantime, wash and de-stem the kale and tear the leaves into bite-sized pieces. Place the leaves on a clean kitchen towel and pat dry. Do your best to get the kale as dry as possible, as this will make crispier kale!
Season: Add the kale to a large bowl and sprinkle the oil, nutritional yeast, garlic powder, salt, and cayenne (if using) on top. Use clean hands to gently massage the seasonings into the kale until all leaves are evenly coated.
Bake the Kale: Spread the kale evenly across a large baking sheet and place in the top rack of the oven. Bake for 5 minutes, then use tongs to give the kale a quick toss on the baking sheet. Bake for an additional 5 to 10 minutes, until the edges of the kale are crispy. Cool time will depend on how wet the kale leaves were — watch them carefully because they can burn quickly! I like to time this so the kale finishes baking at the same time as the casserole. Once crispy, remove the baking sheet from the oven and allow the kale chips to cool and crisp up more on the baking sheet.
Serve & Store: Remove the casserole from the oven and give it a good mix. Divide between serving bowls and top with the crispy kale, or serve the kale on the side and sprinkle on top as you enjoy the meal. Store any casserole or kale leftovers in separate airtight containers in the fridge for up to 5 days.