Smita Chandras Malabar Mussels

Name: Smita Chandra’s Malabar Mussels
Ingredients: 3 tbsp. canola oil; 6 cloves garlic, thinly sliced; 2 small green Thai chiles or 1 serrano, thinly sliced; 1 (2″) piece ginger, peeled and thinly sliced; 2 tsp. Malabar masala; 3 plum tomatoes, chopped; 1 (14-oz.) can coconut milk; Kosher salt, to taste; 2 1⁄2 lb. mussels, debearded and scrubbed; 1⁄4 cup roughly chopped cilantro; Cooked white rice, for serving (optional); 1⁄2 small red onion, thinly sliced