Line loaf tin with baking paper
Cut puff pastry into rectangles and line sides of cake tin with these (ensuring a little overhand at the top).
Cut pizza base same size as the bottom of the cake tin and place one slice on the baking paper (this will be the bottom layer). On pizzas base add 2 tablespoons pizza sauce, spread evenly. Add 2 slices ham and about 5-6 slices pepperoni, sprinkle 1/3 of the cheese over the top.
Cut the next piece of the pizza base to fit the cake tin and then repeat step 2, continuing to layer until you have 3 layers (if you want more just use extra ingredients).
Fold over excess puff pastry.
Place tin in slow cooker and cook on high for 2 hours (approximately), with tea towel under the lid.
To brown place under 200 degree Celsius grill for 5 minutes