One Pot Veggie Mac and Cheese Recipe

Name: One Pot Veggie Mac and Cheese Recipe
Ingredients: 2 cups elbow macaroni (or your favorite pasta); 2 tablespoons butter; 1 medium onion, finely chopped; 1 cup carrots, shredded or finely chopped; 1 cup broccoli florets, chopped small; 2 1/2 cups milk (whole, 2%, or a non-dairy alternative); 1 1/2 cups shredded cheddar cheese; 1/2 cup grated Parmesan cheese; Salt and pepper to taste; 1 teaspoon garlic powder (optional); 1 teaspoon mustard powder (optional); Fresh parsley or chives for garnish (optional)