Preheat the oven to 350°F (175°C).
Heat oil in a large skillet over medium heat. Add taro root and garlic powder, cooking until softened, about 5 minutes, stirring occasionally.
Mix in carrots, breadcrumbs, salt, and pepper; remove from heat and cool slightly.
Combine onion and soy sauce in a separate bowl; stir into taro root mixture.
Divide mixture into four equal portions, forming each one into a patty; place on parchment paper-lined baking sheet. Bake for 20 minutes, flipping once after 10 minutes.
Toast burger buns in the toaster or oven-safe skillet over medium heat.
Assemble burgers with patty, and fill with your favorite toppings.