Servings: 4 servings 2 Tbsp olive oil 8 oz penne pasta 1 bell pepper, any color, sliced into strips 1 medium zucchini, sliced into rings 6 oz brown or white mushrooms, sliced 1/2 medium red onion, sliced ¾ tsp fine sea salt, or to taste, plus more for boiling pasta ¼ tsp ground black pepper, or to taste 3 Tbsp unsalted butter 3 garlic cloves, minced 2 Tbsp lemon juice, freshly squeezed 1/2 cup freshly grated parmesan cheese, plus more to serve 2 Tbsp chopped fresh parsley, to serve
Cook pasta in salted water according to package instructions until al'dente or to your desired doneness, drain water and cover to keep warm.
While the pasta cooks, cook the vegetables: place a large deep skillet or dutch oven over medium-high heat and add oil. Add bell peppers, zucchini, mushrooms, and red onion and saute tossing and stirring frequently until vegetables are crisp-tender, 6-8 minutes.
Season with salt and black pepper, to taste. Reduce heat to medium and add the butter and garlic and cook until garlic is fragrant, about 1 minute.
Add the pasta, lemon juice, and parmesan cheese to the skillet. Toss to combine. Season with salt and pepper to taste. Once pasta is heated through, remove from heat.
Garnish with more freshly grated parmesan if desired and sprinkle on parsley.