Preheat your oven to 400°F (200°C). Toss the chopped vegetables with a tablespoon of olive oil, salt, and pepper, then spread them on a baking sheet. Roast until tender and caramelized around the edges, about 25-30 minutes.
While the veggies roast, sauté minced garlic in a teaspoon of olive oil in a large skillet until fragrant, about 1 minute. Add the chopped sage and cinnamon, cooking for another 30 seconds to infuse the aroma.
Add the roasted vegetables to the skillet and toss gently to coat them with the fragrant herbs and spices. Cook for 2-3 minutes to meld flavors.
Transfer the vegetable mixture into a greased baking dish, spreading it evenly. Sprinkle the shredded cheddar and grated Parmesan cheese over the top.
Combine breadcrumbs with a teaspoon of olive oil and a pinch of salt to create a crisp topping. Sprinkle this evenly over the cheese layer.
Bake the casserole in the preheated oven until the cheese is bubbly and golden, about 20-25 minutes. The topping should be crispy and browned, signaling it's ready to serve.
Remove from the oven and let it rest for 5 minutes before serving. This helps the layers set slightly and makes serving easier.
Slice into portions and enjoy this hearty, flavorful fall casserole that combines tender roasted vegetables with cheesy goodness and a crispy topping.
