Spiced Dal with Fluffy Rice and Salted Yogurt

Name: Spiced Dal with Fluffy Rice and Salted Yogurt
Ingredients: 2 tablespoons ghee, virgin coconut oil, or vegetable oil; 1 medium yellow onion, finely chopped; 1 (2-inch) piece ginger, peeled, finely grated; 2 garlic cloves, finely grated; 1 1/2 cups yellow split peas, rinsed; 2 teaspoons ground coriander; 1 teaspoons ground turmeric; 1/2 teaspoon ground cardamom; Pinch of crushed red pepper flakes; Kosher salt; 1 lime; 1 small red onion, very thinly sliced into rounds, rinsed; Pinch of sugar; 1/2 cup plain whole-milk Greek yogurt; Cooked Jasmine or basmati rice (for serving); Freshly ground black pepper