Lightly grease the slow cooker with olive oil.

In a small bowl, mix together the Alfredo sauce and pesto.

Spread a small amount of the Alfredo-pesto sauce at the bottom of the slow cooker.

Layer half of the frozen cheese ravioli over the sauce.

In another bowl, combine the shredded chicken with the remaining Alfredo-pesto sauce.

Spread half of the chicken mixture over the ravioli.

Add dollops of ricotta cheese over the chicken mixture.

Sprinkle with half of the mozzarella and Parmesan cheese, and a bit of Italian seasoning.

Repeat the layers with the remaining ravioli, chicken mixture, ricotta, and cheeses.

Cover and cook on low for 4-6 hours until the ravioli is tender and the cheese is bubbly.

Garnish with fresh parsley before serving, if desired.

For a vegetarian version, omit the chicken and add sautéed mushrooms or spinach for an earthy flavor. If you prefer a spicier kick, consider adding a pinch of red pepper flakes to the sauce. For a more robust flavor, use a smoked mozzarella or add a layer of sun-dried tomatoes. Experiment with different types of pesto, such as sun-dried tomato pesto or arugula pesto, to give the dish a unique twist.