Step 1

FOR THE SAUCE: Adjust oven rack to middle position and heat oven to 400 degrees. Heat oil in large saucepan over medium heat until shimmering. Add garlic and cook until lightly browned, about 1 minute. Stir in tomatoes, tomato sauce, pepper flakes, and salt. Bring to simmer and cook until flavors have melded, about 5 minutes. Remove from heat; cover to keep warm.

Step 2

FOR THE MEATLOAF: Spray broiler-safe 13 by 9-inch baking dish with vegetable oil spray. Place saltines in large zipper-lock bag, seal bag, and crush saltines to fine crumbs with rolling pin. Whisk saltines, milk, and eggs together in large bowl. Let sit until saltines are softened, about 5 minutes. Whisk saltine mixture until smooth paste forms. Add beef, sausage, Parmesan, granulated garlic, oregano, salt, pepper, and pepper flakes and mix with your hands until thoroughly combined.

Step 3

Transfer beef mixture to prepared dish. Using your wet hands, shape into 9 by 5-inch rectangle; top should be flat and meatloaf should be 1½ inches thick. Pour sauce over meatloaf. Cover dish with aluminum foil and place on rimmed baking sheet. Bake until meatloaf registers 160 degrees, 1 hour 5 minutes to 1¼ hours.

Step 4

Remove sheet from oven, uncover dish, and sprinkle meatloaf evenly with fontina. Heat broiler. Broil meatloaf until cheese is melted, about 2 minutes. Let rest for 15 minutes.

Step 5

Using 2 spatulas, transfer meatloaf to cutting board. Spoon off any excess grease from tomato sauce. Slice meatloaf 1 inch thick. Transfer slices back to sauce in baking dish, sprinkle with basil, and serve.