In a bowl, mash the potatoes. Add the dry ingredients, 1 Tsp Red Chili Powder, 1 Tsp Cumin Powder, salt according to your taste, and 1 Tsp Chaat Masala. Mix them well.
Now, add the chopped coriander leaves and mix them well.
Take the slices of bread. Apply butter on both sides and add a layer of mashed potato on one side.
Now, add some layers of the sliced veggies on top of mashed potatoes.
Grate some cheese on top and cover it with another buttered slice of bread.
Take a Tawa, add some butter in the center of the Tawa, toast the sandwich. Using a spoon, press it gently so that it sticks together. (I have used a stovetop toaster.)
Toast it until both sides turn crispy. Your aloo toast is ready. Serve it with tomato ketchup or green chutney.