Preheat the oven to 400°F (200°C). Line a baking sheet with parchment paper.
Brush the cut sides of the butternut squash halves with 1 tablespoon of olive oil and the honey. Season with 1/2 teaspoon of salt and 1/4 teaspoon of black pepper.
Place the squash cut-side down on the prepared baking sheet and roast for 40 to 45 minutes, or until fork-tender.
While the squash roasts, heat the remaining 1 tablespoon of olive oil in a large skillet over medium heat. Add the chopped onion and minced garlic, sautéing for 3 minutes until softened.
Add the diced chicken breast to the skillet, seasoning with the remaining 1/2 teaspoon of salt and 1/4 teaspoon of pepper. Cook for 6 to 8 minutes until the chicken is browned and cooked through.
Stir in the fresh spinach and dried cranberries, cooking for another 2 minutes until the spinach wilts. Remove from heat.
Once the squash is tender, remove from the oven and carefully flip the halves over. Scoop the chicken filling evenly into the cavity of each squash half.
Top with grated Parmesan cheese and return to the oven for 5 minutes until the cheese is melted and lightly golden. Serve warm.