Preheat oven to 375 degrees Fahrenheit. Grease a 9x13 inch baking dish with cooking spray or butter.

In a large bowl, combine ricotta cheese, egg, Parmesan cheese, minced garlic, Italian seasoning, and a pinch of salt and pepper. Mix until well combined.

Heat a large skillet over medium heat. Add chopped spinach and cook for 3-4 minutes until wilted. Drain excess liquid and stir spinach into the ricotta mixture.

Spread 1/2 cup marinara sauce on the bottom of the prepared baking dish. Arrange half of the dumplings in a single layer. Spread half of the ricotta-spinach mixture over dumplings, then add 1/2 cup marinara and 1 cup mozzarella cheese.

Repeat layering with remaining dumplings, ricotta-spinach mixture, marinara sauce, and top with remaining 1 cup mozzarella cheese.

Cover the dish with aluminum foil and bake for 25 minutes. Remove foil and bake for an additional 10 minutes until cheese is golden and bubbly.

Let the dumpling lasagna rest for 5-10 minutes before slicing. Garnish with fresh basil if desired and serve hot.