In a skillet, heat olive oil and 1 tablespoon of butter over medium heat. Add sliced onions and a pinch of salt. Cook, stirring frequently, until the onions are caramelized, about 15-20 minutes.

Make the Cheese Sauce

In a large pot, melt the remaining 1 tablespoon of butter over medium heat. Add the blue cheese, cheddar cheese, and Gruyère cheese. Stir until melted and smooth. Season with salt and black pepper.

Combine Ingredients

Add the cooked pasta, lobster meat, caramelized onions, and chopped basil to the cheese sauce. Stir until well combined and heated through.

Prepare the Panko Topping

In a small bowl, mix panko breadcrumbs with a drizzle of olive oil, salt, and pepper.

Assemble and Bake

Transfer the lobster mac mixture to a baking dish. Sprinkle the panko mixture evenly over the top. Bake in a preheated oven at 350°F (175°C) for 20-25 minutes, or until golden and bubbly.

Serve

Let cool slightly before serving. Garnish with additional basil if desired.