For the Pesto Bechamel:

1. In a large oven-safe skillet, heat the oil over medium-high heat.
2. Add the onion and saute until it begins to soften, about 5 minutes. Stir in the garlic and cook for another minute.
3. Sprinkle the flour over the onion and garlic, stir to incorporate, and cook for a minute.
4. Slowly stream in the milk, whisking the entire time and scraping up any browned flour bits on the bottom of the pan. Pour in the broth.
5. Stirring almost constantly, bring the mixture up to a gentle simmer and cook for a few minutes until it is slightly thickened.
6. Stir in the pesto and parmesan and mix to incorporate.
7. Season, to taste, with salt and pepper.

For the Breadcrumb Topping:

1. While the bechamel sauce is cooking, prepare the breadcrumb garnish by heating a small skillet over medium heat and adding the oil.
2. Add in the breadcrumbs and seasonings and cook, stirring constantly, for a few minutes or until the breadcrumbs are golden and crisp.
3. Set aside until it is time to serve.

To Assemble:

1. To the simmering bechamel sauce, add the shredded chicken and stir to incorporate.
2. Add the broken lasagna noodles and stir them into the sauce.
3. Keeping the sauce at a gentle simmer (don’t let it come to a full boil), cook the noodles until they are mostly tender, about 10-15 minutes. During this time, if the sauce starts to get too thick or the noodles look dry, add another few tablespoons of milk or broth.
4. Once the noodles are tender, dollop the ricotta and the pesto evenly over the top of the noodle and chicken mixture.
5. Sprinkle over the mozzarella and parmesan cheeses.
6. Transfer the skillet to the oven and broil for 1-2 minutes, watching it closely the whole time, or until the cheeses are melted and lightly golden brown in spots.
7. Remove from the oven and allow to cool for a few minutes.

To Serve:

Sprinkle the crispy breadcrumbs over the top of the lasagna. Garnish with fresh basil and serve.