Measurements are vague as this was an instagram recipe
1 or 2 tins of beans
Loads of cheese
Potatoes, cubed and boiled until just tender
1 onion, diced
Pastry for a pie dish (probably 325g flour, 160g fat)
Soften onion, then add grated cheese and cooked potatoes, season and stir to combine.
Roll out pastry and layer the cheesy potatoes with beans. Brush rim with egg wash and put lid on pie. Egg wash the top of the pie, poke holes in the top, crimp and bake until golden (180 for ~40 minutes)