Mac And Cheese With Ground Beef

Name: Mac And Cheese With Ground Beef
Ingredients: 2 1/4 cups uncooked elbow macaroni; 1 tablespoon olive oil; 1/2 large onion (finely chopped); 3 cloves garlic (minced); 1 pound ground beef; 3/4 teaspoon salt (plus more, to taste); 1/2 teaspoon black pepper; 3/4 teaspoon paprika; 1/2 teaspoon dried oregano; 1 can diced tomatoes (14 1/2 ounces) (drained); 1 tablespoon tomato paste; 2 tablespoons unsalted butter; 2 1/2 tablespoons all-purpose flour; 1 cup whole milk; 2 cups shredded cheddar cheese; Fresh parsley (chopped, for garnish)