For the potato crust bases:

1. Preheat your oven to 180°C and lightly oil 2 x 6-hole muffin/cupcake tins.
2. Place a potato into each muffin hole and use the bottom of a glass to smash the potatoes into the muffin holes to make mini quiche bases.
3. Drizzle each one with a little olive oil and sprinkle with a little salt, and bake at 180°C for 20 minutes until beginning to brown. 

For the filling:

1. Meanwhile, in a large frypan on medium heat, sauté the leeks and garlic in butter until soft and sweet – about 10 minutes. Toss the ham through and then set aside to cool.
2. Whisk the egg, add the ricotta, cheddar, lemon zest, herbs, salt and pepper and mix to combine, then stir through the cooled leek mix.
3. Pour the filling into the potato pie crusts and top with a little extra cheese. Bake for 20 minutes at 180°C until filling is set and potato edges are crispy.
4. Serve warm with extra ricotta and lemon zest.