Asparagus And Mushroom Spaghetti Squash Quiche

1 spaghetti squash;

13 oz. asparagus, trimmed and cut into 1-inch pieces;

½ red onion, sliced;

1 cup mushrooms, sliced;

2 garlic cloves, minced;

5 eggs;

½ cup coconut milk;

1 tsp. fresh rosemary, minced;

Sea salt and freshly ground black pepper;