Spicy Black Bean and Corn Tacos

Name: Spicy Black Bean and Corn Tacos
Ingredients: 1/4 cup hazelnuts, coarsely chopped; 1/4 cup raw pumpkin seeds; 2 ears of corn, shucked; 1 medium jalapeño, seeded, finely chopped; 1 teaspoon crushed red pepper flakes; 1/4 cup chopped cilantro, plus more for serving; 5 tablespoons olive oil, divided; 5 tablespoons fresh lime juice, divided, plus lime wedges for serving; 1 1/4 teaspoons kosher salt, divided; 1 red onion, coarsely chopped; 2 (15-ounce) cans black beans, rinsed, drained; 1 tablespoon ground cumin; 12 small corn tortillas; 1/2 cup sour cream; 1 large avocado, thinly sliced