Black Bean and Butternut Squash Tacos

Name: Black Bean and Butternut Squash Tacos
Ingredients: 1 1/2 cups refried black beans; 1 small butternut squash; 2 tablespoons olive oil; 1 teaspoon salt; 1/2 teaspoon ground cinnamon; 1 teaspoon ground cumin; 1/2 teaspoon freshly ground black pepper; 8 soft corn tortillas; Pickled Shallots, recipe follows; Cilantro sprigs for serving; 3 Serrano chiles, seeds removed if desired, diced; Crema, creme fraiche or sour cream for serving; 1 cup red wine vinegar; 1 cup dry red wine; 1/2 cup packed brown sugar; 2 tablespoons black peppercorns; 1 tablespoons mustard seeds; 2 teaspoons red pepper flakes; 2 teaspoons coarse salt; 20 medium shallots, peeled