Heat oven to 350 F. Line a 15 x 10-inch baking pan with aluminum foil.

Cut tops off of squash; remove seeds and discard. Brush cut sides of squash with 1 tablespoon olive oil; season with salt and pepper. Place squash, cut side down, on prepared pan. Bake for 40-45 minutes or until tender.

Meanwhile, cook sausage in a large skillet over medium heat until meat is no longer pink; drain. Transfer sausage into a bowl. Wipe out the pan.

Sauté onion in remaining olive oil in the same pan over medium-high heat for 3 minutes. Reduce heat to medium. Add apples and sage; cook and stir for 2-3 minutes or until apples are tender. Stir in the spinach, apple butter and sausage. Cook and stir for 2-3 minutes longer or until heated through. Remove from the heat. Stir in 1 1/2 cups gouda.

Spoon sausage mixture into squash. Bake for 15 minutes. Sprinkle with remaining gouda. Bake for 5-6 minutes longer or until cheese is melted.