Preheat the oven to 375°F.
Cut the zucchini in half length-wise and scoop out the seeds. Rub the outside of the zucchini halves with 1 teaspoon of olive oil and place in a 13x9-inch baking dish.
In a skillet over medium heat, sauté the onion in the remaining olive oil for 2 to 4 minutes, or until soft. Add the garlic and sausage meat. Break the meat into small pieces with a wooden spoon or spatula. Sauté the sausage for 5 minutes, or until it is no longer pink. Drain the excess fat from the pan and discard. Add the salt, pepper, bread crumbs, and cheese to the skillet and mix well.
In a small bowl, mix the egg with the cream. Add to the skillet and stir.
Fill the zucchini halves with the sausage mixture. Cut the halves across the center to make eight filled “boats.” Cover the baking pan with aluminum foil and bake for 25 minutes. Remove the foil and bake for 20 minutes more, or until the zucchini is fork-tender.