Braised Spinach

Name: Braised Spinach
Ingredients: 1/4 cup extra-virgin olive oil; 2 large red onions, sliced; 4 garlic cloves, minced; 4 large bunches fresh spinach, washed with water still clinging to leaves, stems trimmed and leaves coarsely chopped; 2 tablespoons soy sauce; 3/4 teaspoon dried crushed red pepper flakes; Salt and freshly ground black pepper