Preheat your oven to 375°F (190°C).
In a large skillet over medium heat, brown the ground beef. Drain excess fat.
Stir in the marinara sauce and let simmer for about 10 minutes.
In a medium saucepan, melt butter over medium heat. Add flour, whisking until it forms a paste.
Slowly whisk in the milk, ensuring there are no lumps. Cook until thickened, about 5 minutes.
Stir in the chopped chipotle peppers and remove from heat.
In a 9x13 inch baking dish, spread a thin layer of the chipotle bechamel sauce on the bottom.
Layer 3 lasagna noodles, followed by a portion of the beef sauce, a dollop of ricotta, and a sprinkle of mozzarella and Parmesan. Repeat layers twice.
Finish with a generous layer of mozzarella on top.
Cover with foil and bake for 30 minutes. Remove foil and bake for an additional 15 minutes, or until cheese is golden brown and bubbly.
Let cool for 10 minutes before serving.