Preheat oven to 375°F. Cook lasagna noodles according to package directions in an (8-qt.) stockpot, using the shortest cook time. Drain and set aside.

In a small batter bowl, whisk together Alfredo sauce, milk, and dried oregano until well blended. Set aside.

Coarsely chop the cooked chicken. Using a food chopper, chop the artichokes, bell pepper, and onion, placing them in a (4-qt.) stainless mixing bowl. Press garlic over the bowl using a garlic press. Add shredded mozzarella and crumbled feta cheese, mixing well.

To assemble the lasagna, spread 2/3 cup of the Alfredo sauce mixture over the bottom of a rectangular or large baker. Top with half of the cooked noodles, overlapping as needed. Layer half of the spinach leaves over the noodles, then half of the chicken mixture. Repeat layers, starting with half of the remaining sauce. After layering, pour the remaining sauce over the top of the lasagna.

Cover the baker with aluminum foil and bake for 45 minutes. Carefully remove the foil and continue baking for an additional 10-15 minutes or until bubbly. Remove from the oven and let stand for 15 minutes before serving for easier slicing. Cut into squares and serve using a large serving spatula.