Step 1: Preheat your oven to 375°F (190°C). Bring a large pot of salted water to a boil and cook the jumbo shells according to package directions, but remove them 2 minutes before they reach al dente. Drain and rinse with cool water to prevent sticking.
Step 2: In a large skillet over medium heat, cook the diced bacon until it is crispy and the fat has rendered. Use a slotted spoon to remove the bacon to a paper-towel-lined plate.
Step 3: Leave about 2 tablespoons of bacon fat in the skillet. Add the minced shallots and sauté for 5-7 minutes until soft and slightly golden. Add the garlic and cook for another 60 seconds until fragrant.
Step 4: In a large mixing bowl, combine the ricotta cheese, half of the cooked bacon, the sautéed shallot and garlic mixture, 1/2 cup of Parmesan cheese, the egg, parsley, salt, and pepper. Stir until well combined.
Step 5: Spread about 1 cup of the sauce in the bottom of a 9×13 inch baking dish.
Step 6: Stuff each cooked shell with approximately 2 tablespoons of the ricotta mixture and place them in the baking dish in a single layer.
Step 7: Top the stuffed shells with the remaining sauce, followed by the mozzarella cheese, the rest of the Parmesan, and the remaining bacon bits.
Step 8: Cover the dish with aluminum foil and bake for 20 minutes. Remove the foil and bake for an additional 10-15 minutes until the cheese is bubbly and slightly browned. Let rest for 5 minutes before serving.