Preheat oven to 400°F. Toss sweet potato and butternut squash slices with olive oil, salt, and pepper. Roast on a baking sheet for 20 minutes until tender. Reduce oven to 375°F.

In a bowl, mix ricotta, egg, Parmesan, oregano, salt, and pepper.

In a small saucepan, combine cranberry sauce and balsamic vinegar over low heat until smooth for the glaze.

In a 9x13 inch baking dish, spread a thin layer of the ricotta mixture. Layer 3 lasagna noodles, half the roasted vegetables, half the ricotta mixture, half the feta, and half the walnuts. Repeat layers, ending with noodles.

Spread remaining ricotta mixture over top. Cover with foil and bake for 30 minutes. Remove foil, sprinkle with remaining feta and walnuts, and bake uncovered for 10 minutes until golden.

Let lasagna rest for 10 minutes. Drizzle with cranberry glaze and garnish with parsley before serving.