Step 1: Preheat oven to 375 °F (190 °C). Line a baking sheet with parchment paper. Cook spaghetti in salted boiling water until al dente, then drain well.
Step 2: In a large skillet over medium heat, crisp the chopped turkey bacon. Add the ground beef and cook until browned, breaking it up with a spoon. Drain any excess fat. Stir in the 2 cloves of minced garlic, diced chicken ham, Italian seasoning, and tomato pasta sauce. Season with salt and black pepper to taste. Simmer for 3–4 minutes, then remove from heat and toss the cooked spaghetti into the sauce until evenly coated.
Step 3: Slice the top third off the French or Italian loaf lengthwise. Carefully hollow out the soft interior from both the bottom and top halves of the loaf, leaving a ½ inch border of bread on all sides.
Step 4: In a small bowl, blend the softened unsalted butter with the 3 cloves of minced garlic and chopped fresh parsley until combined. Spread this garlic butter mixture evenly inside both the hollowed-out bottom and top halves of the bread loaf.
Step 5: Spoon the spaghetti mixture into the bottom half of the hollowed loaf, pressing gently to create an even layer. Sprinkle the shredded mozzarella cheese generously over the pasta, then place the reserved top half of the bread back on. Wrap the entire stuffed loaf tightly in aluminum foil.
Step 6: Bake the wrapped loaf for 15 minutes. Unwrap the loaf and bake for an additional 5–7 minutes, or until the cheese is melted and bubbly, and the crust is golden brown and crispy.
Step 7: Let the loaf rest for 5 minutes before slicing it into thick pieces. Drizzle with extra marinara sauce if desired, and serve immediately.