2 leeks, thinly sliced (white and pale green parts only)
1 ounce freshly grated Parmesan cheese
salt & pepper
DIRECTIONS
Cook the penne pasta in a dutch oven or large pot of water about 1 minute shy of package directions.
Drain the pasta, reserving about 1/2 cup of the pasta water, and set aside.
Heat the oil in the now empty pot over medium-high heat.
Add the mushrooms and leeks to the pot and cook, stirring occasionally, until mushrooms are browned and leeks are softened, about 5 minutes.
Stir in the cooked pasta, Parmesan, 1/2 tsp salt, and 1/4 tsp pepper. Stir in the reserved pasta water a little at a time until you reach a desired consistency.
Season with additional salt & pepper if necessary.