Udon all'Amatriciana

Name: Udon all'Amatriciana
Cuisine: European, Italian, Mediterranean, Asian
Ingredients: ¼ cup extra-virgin olive oil; 1 small white onion (8 oz.), finely chopped; 10 garlic cloves, thinly sliced (⅓ cup); Two 28-oz. cans whole peeled San Marzano tomatoes; 1 Tbsp. plus 1½ tsp. sugar; 1½ tsp. kosher salt; 4 tsp. sesame oil; 2 large red onions (10 oz.), each cut into 10 wedges; 4½ oz. guanciale, cut into thin matchsticks (1 cup); 2 Tbsp. white miso; 2 tsp. freshly ground black pepper; Pinch crushed red chile flakes; Pinch ichimi togarashi; ¾ cup low-sodium chicken stock; 1½ tsp. soy sauce; Kosher salt; Two 8-oz. packages fresh udon; ⅔ cup (1½ oz.) finely grated Pecorino Romano, plus more for garnish; Crispy garlic, for garnish; Crispy red onion, for garnish; Thinly sliced scallions, for garnish