Vegetable Enchiladas

Name: Vegetable Enchiladas
Ingredients: 2 tablespoons olive oil, plus more for baking dishes; 2 teaspoons ground cumin; ¼ cup all-purpose flour (spooned and leveled); ¼ cup tomato paste; 1 can (14 ½ ounces) reduced-sodium vegetable broth; Coarse salt and ground pepper; 3 cups grated pepper Jack cheese (12 ounces); 1 can (15 ounces) black beans, rinsed and drained; 1 box (10 ounces) frozen chopped spinach, thawed and squeezed dry; 1 box (10 ounces) frozen corn kernels, thawed; 6 scallions, thinly sliced, white and green parts separated; 16 corn tortillas (6-inch)