Prep the zucchini: Slice zucchini lengthwise into thin planks, about 1/8 inch. Use a mandoline for even slices if you have one. Lay slices on paper towels, sprinkle with salt, and let sit 15 minutes to draw out moisture. Blot dry.

Optional pre-cook for firmer layers: Heat a large skillet over medium-high with a light brush of olive oil. Sear zucchini planks 1–2 minutes per side to reduce water. Transfer to paper towels to cool and blot again.

Make the Alfredo sauce: In a saucepan, melt butter over medium heat. Add garlic and cook 30 seconds until fragrant. Whisk in heavy cream and cream cheese, stirring until smooth and slightly thickened, 3–5 minutes.

Finish the sauce: Stir in Parmesan, Italian seasoning, a pinch of salt, and pepper. Simmer gently 1–2 minutes until silky. If it gets too thick, splash in a bit more cream. Remove from heat.

Season the chicken: In a bowl, toss cooked chicken with a spoonful of Alfredo sauce, a pinch of salt, pepper, and red pepper flakes if using. This keeps it juicy and flavorful.

Preheat the oven: Set to 375°F (190°C). Grease a 9x13-inch baking dish or similar.

Layer 1: Spread a thin layer of Alfredo on the bottom of the dish. Add a single layer of zucchini slices, slightly overlapping. Top with half the chicken, a few spoonfuls of Alfredo, and a handful of mozzarella.

Layer 2: Repeat: zucchini, remaining chicken, more Alfredo, and mozzarella.

Top layer: Finish with a final layer of zucchini, the rest of the Alfredo, and the remaining mozzarella. Sprinkle extra Parmesan on top for a golden crust.

Bake: Cover loosely with foil and bake 20 minutes. Remove foil and bake another 12–15 minutes, until bubbly with browned spots.

Rest and slice: Let the lasagna rest 10–15 minutes before slicing. This helps it set and reduces excess moisture.

Garnish and serve: Sprinkle with chopped parsley and cracked black pepper. Serve warm.