Alon Shayas Spanakopita with Collard Greens Jalapeño

Name: Alon Shaya's Spanakopita with Collard Greens & Jalapeño
Ingredients: 1 1/2 pounds collard greens; 1 1/2 pounds mustard greens; 1 teaspoon Morton kosher salt; 1/4 cup extra-virgin olive oil; 2 yellow onions, chopped; 2 jalapeños, seeds and pith removed, minced; 2 cloves garlic, minced; 1/2 cup raw pine nuts or chopped raw walnuts; 1 cup lightly packed fresh dill fronds, chopped; 1 cup lightly packed fresh mint leaves, chopped; 3 cups crumbled feta, preferably Bulgarian; Grated zest of 1 lemon; 1 tablespoon lemon juice; 1 teaspoon finely grated nutmeg; 1 teaspoon freshly ground black pepper; 4 eggs, lightly beaten; 1 pound phyllo dough, defrosted; 1/2 pound unsalted butter, melted (2 sticks); 3/4 cup grated Pecorino Romano cheese