"Paneer tikka sandwich is a popular afternoon snack that people like to have with hot or cold coffee. Its simple and quick to make, and you can add other toppings, like bell peppers or carrots as well."
Heat oil in a large skillet over medium heat. Add onions; cook and stir until softened, about 5 minutes. Stir in chile powder, garam masala, turmeric, sugar, and salt. Add paneer and tomato sauce; cook and stir until flavors combine, 3 to 5 minutes.
Spread 1 teaspoon butter and 2 tablespoons of the paneer filling over 1 slice of bread. Place second slice of bread on top.
Melt remaining 1 teaspoon butter in a large skillet over medium heat. Add sandwich; cook until golden brown, about 1 minute per side.