“Purple potato, tuna and rocoto pepper causa. Causas are cold mashed-potato salads, topped usually with avocado and other ingredients. We love making them, and this one has been a real favorite as a result of its balance of textures, colors, and flavors. You can use cooked octopus or any other fresh fish instead of tuna, if you prefer.”– Martin Morales
Recipe excerpted with permission from Andina: The Heart of Peruvian Food by Martin Morales, published by Quadrille. Click here to purchase your own copy.
- 200 grams purple potatoes or regular floury potatoes
- 3 tablespoon ají amarillo paste
- 1 tablespoon lime juice
- 2 tablespoons olive oil
- a few purple shiso leaves or small basil leaves, to decorate
- salt and freshly ground black pepper
For the Tuna Tartare
- 50 milliliters rocoto tiger’s milk, plus extra (optional) for drizzling
- 1 tablespoon mayonnaise
- 150 grams tuna fillet, chilled and finely chopped
For the Avocado Purée
- 1 large ripe avocado
a squeeze of lime juice
For the Ají Amarillo Paste
- 1 tablespoon olive oil
- 1/4 onion, finely chopped
- 2 garlic cloves, finely chopped
- 2 ají amarillos, or 2 medium-heat red chiles and 1/2 yellow pepper, deseeded and finely chopped
For the Rocoto Tiger’s Milk
- 5 milliliter slice of ginger, bruised
- 1 garlic clove, halved and bruised
- 4 coriander sprigs, roughly chopped
- Juice of 12 limes, plus extra to taste
- 1/2 rocoto pepper or 2 medium-heat red chiles, deseeded and chopped
- First, cook the potatoes. Leave them in their skins, put them in a large saucepan and cover them with water. Put the pan over a high heat and bring to the boil, then cook the potatoes until just tender (about 15–20 minutes). Remove the pan from the heat and drain. When they are cool enough to handle, peel them and mash the flesh. Add the chile paste to the mash, along with the lime juice and olive oil and season well with salt and pepper. Allow to cool.
- To make the tuna tartare, whisk together the rocoto tiger’s milk and the mayonnaise, then season with salt and pepper. Add the tuna and stir to combine, then cover and leave the tartare to chile in the fridge until you are ready to serve.
- To make the avocado purée, halve the avocado, remove the stone and peel the halves. Put the avocado flesh with the squeeze of lime juice and a pinch of salt in a food processor or blender and blitz until smooth.
- To assemble the dish, divide the potato mixture into 4 equal portions and shape each into a round patty, like a burger. Place one patty on each of 4 plates. Spoon a quarter of the avocado purée on top of each patty, then top with equal portions of the tuna tartare and drizzle with a little more rocoto tiger’s milk, if you wish. Decorate with the shiso leaves and serve immediately.
- For the ají amarillo paste, heat the oil in a small frying pan over a low–medium heat. Fry the onion for 7–8 minutes until soft, but not browned, then add the garlic and chile (or alternative) and fry for 2–3 minutes more to soften. Season with salt to taste, then allow to cool completely. When cool, blitz to a smooth paste, then set aside until needed. (You can store any leftover in an airtight container the fridge for up to 1 week.)
- To make the rocoto tiger’s milk, put the ginger, garlic, coriander and lime juice in a bowl. Allow to infuse for 5 minutes, then strain. Add the rocoto pepper or chile to the liquid and add 1/2 teaspoon of salt. Transfer the mixture to a food processor or blender and blitz until smooth. Taste and adjust the salt and lime juice as necessary.