Chile con Queso

Ingredients

• 2 teaspoons extra-virgin olive oil
• 1 medium onion, chopped
• 2 cloves garlic, minced
• 1/2 cup pale ale (or other light-colored beer)
• 1 1/2 cups low-fat milk, divided
• 3 tablespoons cornstarch
• 1 3/4 cups shredded sharp cheddar, preferably orange
• 1 10-ounce can diced tomatoes with green chiles, drained or 1 1/4 cups drained petite-diced tomatoes (see note below)
• 2 tablespoons lime juice
• 1 teaspoon salt
• 1 teaspoon chili powder
• cayenne pepper to taste (optional)
• 1/4 cup sliced scallions
• 2 tablespoons chopped fresh cilantro