peel and slice the potatoes

boil the potatoes add the leaves of basil and s pinch of salt

in a saucepan cook for a few minutes the onions and capsicums

chop in small pieces the capsicum and onion

add the tomato paste and the seasonings you can add a little bit of white wine

if the mix is to thicker add a little bit of water

in a oven proof recipient add the butter in the surface and sparse the flour (avoid the mix get stick in the recipient)

start to build the pastel by covering the base with a layer of potatoes, them sparse cheese,them cover the surface with a layer of tuna mix.( how many layers you will do, is a personal choose) but the last layer has to be a potatoes one. to finalise it cover the top with cheese

optional u can add in the top a few slice of tomato to decorate the pastel

put the pastel in the oven (could be at 350°f )for a few minutes till the top of the pastel looks crispy