Butternut Squash Tart (Butternut Squash Recipe)

Name: Butternut Squash Tart (Butternut Squash Recipe)
Prep time: 1 h 45 min
Cook time: 30 min
Total time: 2 h 15 min
Cuisine: American, Mediterranean
Ingredients: 30 grams unsalted butter (2 tablespoons); 300 grams onions, peeled and sliced into thin rings (2 medium onions); 175 grams butternut squash (about 1 1/3 cups, diced); 1 cinnamon stick, broken in half; Salt and pepper, to taste; 15 milliliters olive oil (1 tablespoon); 230 grams butternut squash, cut into 3/4-inch cubes (about 2 cups); 80 grams baby spinach leaves (4 cups); 1/4 teaspoon chili flakes; 1 sheet puff pastry, trimmed to approximately 9 x 13 inches in size; 100 grams blue cheese, crumbled (3 1/2 ounces); 15 grams shaved or grated Parmesan (2 tablespoons); 1 egg, lightly beaten; 2 grams chopped fresh rosemary (1 tablespoon)