Step 1
Heat butter in a pan over medium-low heat. Saute onion until soft, translucent, and slightly caramelized, about 10 minutes. Add apple, garlic, curry powder, tomato paste, flour, garam masala, and ginger. Stir while allowing spices to bloom and flour to cook, 2 to 3 minutes. Add 2 cups coconut milk, carrots, and potato; bring to a boil. Add 4 cups broth, brown sugar, soy sauce, and Sriracha; return to a boil.