Bring a large pot of lightly salted water to a boil; add penne and cook, stirring occasionally, for 6 minutes. Add sugar snap peas to pasta; cook until pasta is tender yet firm to the bite, about 3 minutes more. Drain.
Return pot to stove and heat olive oil and margarine over medium heat. Add mushrooms, green onions, garlic, and lemon zest; cook and stir until fragrant, about 2 minutes. Stir in lemon juice and season with salt and pepper. Add cooked pasta and sugar snap peas; toss to coat. Top with Parmesan cheese and mint.