Preheat oven to 350 degrees
In a large skillet, brown the ground sausauge until it is brown and crumbly. Remove from heat and drain any excess fat.
Fill a large pot with water and bring to a boil. Add in the jumbo shells and cook until they’re relatively soft. You want them to be pliable, but not too soft that they fall apart when stuffing them. Once they’re done cooking, remove from the boiling water and set aside.
In a large bowl, combine the ricotta cheese, half the mozzarella cheese, eggs, garlic powder, and oregano. Stir until combined.
Chop the spinach into fine pieces, stir into the cheese mixture.
In the 9x13 pan, spread half of the spaghetti sauce.
With a large spoon, carefully spoon the cheese mixture into each jumbo shell. Place the shells open side up and close together in the 9x13 pan. Sometimes I run out of room when filling the 9x13 dish. You can always start another pan OR freeze the extra stuffed shells for later.
Layer the rest of the spaghetti sauce over the top of the stuffed shells.
Sprinkle the browned sausage over the top of the whole dish.
Add the remaining mozzarella cheese over the top of the entire dish.
Cover the 9X13 pan with aluminum foil and bake for 35-40 minutes. You will want the cheese to be bubbly. Remove the pan from the oven and let sit for 10 minutes before serving. This will thicken everything up and make the tastiest dinner!