How to Make It
Preheat oven to 475°F. Using your hands, gently mix sausage, eggs, bread crumbs, ½ teaspoon of the salt, and ¼ teaspoon of the pepper in a medium bowl until just combined. Form mixture into 12 1½-inch balls and place on a foil-lined rimmed baking sheet. Bake until cooked through, 10 to 12 minutes.
Meanwhile, heat oil in a medium skillet over medium. Add garlic and cook, stirring constantly, until fragrant, about 30 seconds. Stir in tomatoes and remaining ½ teaspoon salt and ¼ teaspoon pepper. Reduce heat and simmer until slightly thickened, 8 to 10 minutes.
Add meatballs to sauce and toss to coat. Move oven rack 6 inches from heat and increase heat to broil.
Place bottom half of bread, cut side up, on baking sheet. Top with meatballs, sauce, and cheese. Broil until cheese is melted, 2 to 3 minutes. Remove from oven and top with basil. Cover with top half of bread and cut into 4 pieces.