Bring a large pot of salted water to a boil; add lasagna noodles and cook for 4 to 5 minutes. Drain, toss in 1 tablespoon olive oil in the lasagna pot or in a large bowl, and set aside.

Drizzle olive oil on a large skillet; place over medium heat and sauté garlic until fragrant, about 30 seconds. Add 2 C spinach and cook until just wilted, about 3 mins. Remove from the pan and roughly chop the spinach; add to a small bowl and stir in ricotta and ¼ C Parmesan. Season with salt and pepper. Set aside.

Cook sausage in the same skillet over medium until browned and cooked through, breaking it into crumbles, about 5 mins. Add artichokes and sauté for 2-3 mins. Pour in cream and bring to a gentle simmer. Season with salt, pepper, and red pepper flakes. Simmer until slightly thickened, 2-3 mins, then stir in remaining spinach and cook until just wilted.

Pour sausage mixture into lasagna noodles. Stir in ½ C Parmesan and half of mozzarella. Mix until cheese is melted and lasagna noodles are fully coated.

Preheat the oven to 425 degrees F. Lightly grease a 18x13-inch baking sheet or 9x13-inch baking dish. Spread pasta mixture evenly across the prepared pan. Dollop ricotta-spinach mixture over the top. Sprinkle mozzarella and Parmesan evenly across the entire surface.

Bake in the oven until bubbling and golden, 15-20 mins. Optionally, for a more golden crust, turn on the oven's broiler and broil the top for 1-2 mins at the end. Let cool slightly, garnish with fresh herbs, and cut into squares to serve.