Boil the potatoes either by pressure cooking them or steaming them until soft
Peel, mash, and set aside 2 cups
If you plan to add green peas, place 1/4 cups in a microwave-friendly container, add enough water to cover it, and microwave on high for 2-3 mins or until cooked. Set aside.
Heat 1 tbsp oil in a pan and add the 1/2 cup sliced onions
Fry until light golden brown and the edges brown a bit
Add all the spices - 3/4 tsp ginger garlic paste, 1/2 tsp chilli powder (adjust to taste), 1/4 tsp turmeric powder, 1/4 tsp cumin powder, and 1 tsp coriander powder
Fry until the spices are roasted and the onions turn a dark golden brown
Add the peas and mashed potatoes
Mix well, add salt and lemon juice, and mix again
If you have some coriander leaves handy, chop some and throw them in
Mix again well and set aside to cool down
Meanwhile, remove the crust from the bread slices
Using a rolling pin, roll each bread slice as flat as possible
Place 1-2 tsp of the potato filling on one end and roll tightly inwards
Place some water along the other edge and seal
Place sealed side down so the rolls won't open
Proceed with the remaining bread slices and filling
Spread a generous amount of butter on the rolls
Toast the bread rolls until nicely browned and crisp outside
Serve bread potato rolls hot with ketchup