Bring a large pot of salted water to a boil. Add 8 ounces of elbow macaroni and cook until al dente. Drain well and set aside.
In a medium saucepan over medium heat, melt 2 tablespoons of unsalted butter. Whisk in 2 tablespoons of all-purpose flour and cook for 1-2 minutes until bubbly and slightly golden.
Gradually whisk in 1 cup of milk, cooking until the sauce thickens, about 3-5 minutes. Remove from heat and stir in 2 cups shredded white cheddar cheese until melted. Season with 1/2 teaspoon garlic powder, 1/2 teaspoon onion powder, salt, and pepper to taste.
Add the drained macaroni to the cheese sauce and stir gently until evenly coated.
In a mixing bowl, toss 1 cup of breadcrumbs with 2 tablespoons olive oil and 1/4 cup grated Parmesan cheese until evenly coated.
Transfer the mac and cheese mixture to an oven-safe baking dish. Sprinkle the breadcrumb mixture evenly over the top. Bake at 350°F (175°C) for 15-20 minutes until golden brown and crispy.
Remove from oven and let cool slightly. Garnish with chopped parsley before serving.
