1. Preheat your oven to 170°C on convection and coat your 12-cup muffin tray with non-stick cooking spray or brush with olive oil.
2. Peel the potatoes. Slice them into thin, 1mm thick slices using a knife or mandoline.
3. In a large bowl, combine the melted butter, oil, garlic, parmesan, and a large pinch of salt and pepper.
4. Add the potato slices and toss in the butter and oil mixture until well coated.

For Truffle Stacks:

1. Thinly slice your truffles, into wafer-thin rounds, using either a mandolin, very sharp knife or truffle shaver.
2. Save a little truffle for your truffle mayo for serving.
3. Layer the potato slices evenly in the muffin tin, adding a slice of truffle every few layers, until the potato slices just reach above the surface. The potatoes will shrink once cooked.

For Caviar Stacks: 

1. Layer the potato slices evenly in the muffin tin, until they just reach above the surface. The potatoes will shrink once cooked.

1. Cover the muffin tray with foil and transfer it to the oven. Roast the covered potatoes at 170°C for 20 minutes, then remove the foil.
2. Lower the heat slightly to 165°C, and cook for a further 45-60 minutes or until deeply golden and crispy.
3. Cover the muffin tray with foil and transfer it to the oven. Roast the covered potatoes at 170°C for 20 minutes, then remove the foil.
4. Lower the heat slightly to 165°C, and cook for a further 45-60 minutes or until deeply golden and crispy.
5. Tips for success: For even and compact stacks, remove the stacks from the oven once softened, and press them down gently with the back of a spoon. This will press the layers together aiding the presentation
6. If the stacks are getting golden on top but are pale on the bottom, use a silicone spatula to flip them over to aid with even browning
7. If you like your potatoes extra crispy; keep them in the oven for a bit longer until they turn deep golden brown.
8. Remove the potato stacks from the muffin tray and onto a paper towel to drain off excess butter.

For Truffle Stacks:  

1. Finely grate half your remaining truffle with a microplane, and mix it into 80ml mayonnaise. Season the mayonnaise with salt (if needed) to really bring out the truffle flavour. Spoon the truffle mayo onto the potato stacks, and finish with a little extra grated truffle if you have it. Serve immediately.

For Caviar Stacks:

1. Spoon blobs of sour cream onto your potato stacks, top with a spoon of caviar, and finish with chives. Serve immediately.