1. Preheat the oven to 200 degrees and prepare the broth. Slice the onion and crush or finely chop the garlic. Remove the seeds from the red pepper and slice it. Cut the tomato.
2. Heat the wok or sauté pan over medium-high heat and cook the ground beef without oil for about 3 minutes, breaking it up with a spoon. Season with salt and pepper. Set aside.
3. Heat the butter in the same wok and sauté the onion, garlic, and red pepper over medium-low heat for 2 minutes. Add the flour and stir for 2 minutes over medium heat. Add 1/3 of the broth and whisk until incorporated. Repeat this step twice with the remaining broth. Mix until you have a smooth sauce, then add the tomato. Bring to a boil and cook for 1 minute.
4. Add the paprika, cream, ground beef, and 1/3 of the grana padano. Season with salt and pepper.
5. Grease the baking dish with olive oil. Start by spreading a thin layer of sauce in the dish. Cover it with a layer of lasagna sheets and press firmly. Repeat this step, alternating sauce and lasagna sheets, until you have almost used up all the sauce. Finish the lasagna with a layer of sauce and the remaining grana padano. Bake the lasagna for 20 to 25 minutes. Meanwhile, separate the basil leaves.
6. Serve the lasagna on plates and garnish with basil leaves.