Start by thoroughly cleaning and slicing your leeks and mushrooms.

In a large skillet, melt butter over medium heat. Add the sliced leeks and cook until soft and golden brown, about 10-15 minutes.

Stir in the sliced mushrooms and cook for another 5-7 minutes until tender.

Lower the heat and add cream, followed by Gruyere cheese. Stir continuously until melted and smooth.

Cook your chosen pasta in a separate pot according to package directions.

Drain the pasta and toss it with the leek and mushroom sauce, adding reserved pasta water until desired consistency.

Garnish with fresh herbs or additional cheese before serving.