Place the acorn squash halves, cut side u, on a foil-lined baking sheet. Drizzle the four squash halves with 1 tablespoon olive oil and rub to coat. Roast the squash for 30-35 minutes until tender. Remove from the oven and set aside to cool.
Place the raisins in a small heat-safe bowl and cover with boiling water. Cover the bowl with foil and let steep for about 5-10 minutes, or until the raisins are plumped. Drain well and set the raisins aside.
Heat the remaining tablespoon of olive oil in a large skillet over medium-high heat. Sauté the onion, garlic, and bell pepper until tender (3-5 minutes). Add the rosemary and sauté for another minute. Add the spinach and cook until wilted, stirring continuously (2-3 minutes). Transfer the cooked vegetables to a bowl and add the raisins; toss to combine.
When the squash is cool enough to touch, working one at a time, carefully scoop out the flesh of the squash, making sure not to tear the skin.
In a medium mixing bowl, mash the squash with 1/8 teaspoon salt. Add 1/3 cup of the vegetable raisin mixture, ¼ of the cottage cheese, and a few grinds of fresh black pepper, and mix together. Spoon the mixture back into the squash bowl and top with ½ tablespoon of Parmesan cheese. Repeat with the remaining squash bowls. Place all of the filled squash bowls on a lined baking sheet and broil until the cheese is melted (1-1 ½ minutes). Make sure the cheese doesn’t burn. Serve immediately. Refrigerate leftovers.