• Prepare the Oven: Start by heating your oven to 375°F (190°C). Lightly grease a 9x13-inch baking dish and set it aside for later use.

Prepare the White Sauce:

• In a medium-sized saucepan, melt the butter over medium heat.
• Once melted, whisk in the flour and cook for about 1-2 minutes until it turns a light golden color.
• Slowly incorporate the milk and chicken broth, whisking constantly to ensure a smooth mixture without any lumps.
• Season with salt, pepper, and garlic powder, and stir in the parmesan cheese and dried parsley.
• Simmer for 5-7 minutes until the sauce thickens, then set aside.

Prepare the Ricotta Mixture:

• In a large bowl, mix the ricotta cheese, grated parmesan, eggs, salt, pepper, and garlic powder until well combined.
• Stir in the thawed and drained spinach.

Assemble the Lasagna:

• Pour a light coating of the white sauce onto the bottom of the greased baking dish, ensuring an even layer.
• Add a layer of lasagna noodles, then spread a layer of the ricotta-spinach mixture over the noodles.
• Sprinkle a layer of shredded chicken, then place 6 slices of provolone cheese over the chicken.
• Pour a thin layer of the white sauce over the cheese.
• Repeat layers until all ingredients are used, finishing with a final layer of noodles, sauce, and provolone on top.

Bake:

• Cover the dish with aluminum foil and bake for 25 minutes.
• Remove the foil and bake for an additional 10-15 minutes, until the cheese on top is golden and bubbly.

Serve:

• Allow the lasagna to rest for 10 minutes before slicing. Serve warm, and enjoy!